Liquid crystal composition, liquid crystal display device, and liquid crystal display

ABSTRACT

There is provided a liquid crystal composition containing any one or two or more of compounds represented by general formula (i) below and any one or two or more of compounds represented by general formula (ii) below.

TECHNICAL FIELD

The present invention relates to a nematic liquid crystal compositionuseful as a liquid crystal display material and exhibiting a positivevalue of dielectric anisotropy (Δ∈), and also relates to a liquidcrystal display device and liquid crystal display using the composition.

BACKGROUND ART

Liquid crystal display devices have been used for watches and electroniccalculators, various measuring apparatuses, automotive panels, wordprocessors, electronic notebooks, printers, computers, televisions,watches, advertising displays, etc. Typical examples of a liquid crystaldisplay mode include a TN (twisted nematic) mode, a STN (super twistednematic) mode, a vertical alignment mode and an IPS (in-plane switching)mode using TFT (thin-film transistor), and the like. Liquid crystalcompositions used for these liquid crystal display devices are requiredto have stability to external stimuli such as moisture, air, heat,light, and the like, exhibit a liquid crystal phase within as wide atemperature range as possible including room temperature as a center,and have low viscosity and low drive voltage. Further, each of theliquid crystal compositions is composed of several types to several tenstypes of compounds in order to have optimum values of dielectricanisotropy (Δ∈) and/or refractive index anisotropy (Δn) for a displaydevice.

A vertical alignment (VA)-mode display uses a liquid crystal compositionhaving negative Δ∈, while a horizontal alignment-mode display, such as aTN mode, a STN mode, an IPS (in-plane switching) mode, or the like, usesa liquid crystal composition having positive Δ∈. Also, there has beenreported a driving method in which a liquid crystal composition havingpositive Δ∈ is vertically aligned with no voltage applied, and displayis performed by applying a transverse electric field, and the need for aliquid crystal composition having positive Δ∈ is further increased. Onthe other hand, low-voltage driving, fast response, and a wide operatingtemperature range are required for all driving methods. That is, a largeabsolute value of positive Δ∈, low viscosity (η), and a highnematic-isotropic liquid phase transition temperature (Tni) arerequired. Also, in order to set Δn×d which is the product of Δn and acell gap (d) to a predetermined value, it is necessary to adjust Δn of aliquid crystal composition within a proper range according to the cellgap. In addition, when a liquid crystal display device is applied to atelevision or the like, fast response is regarded as important, and thusa liquid crystal composition having low rotational viscosity (γ₁) isrequired.

A liquid crystal composition disclosed as a configuration of a fastresponse-oriented liquid crystal composition uses, for example, acompound represented by formula (A-1) or formula (A-2) below, which is aliquid crystal compound having positive Δ∈, in combination with a liquidcrystal compound represented by formula (B) below having neutral Δ∈. Theliquid crystal composition is characterized in that the liquid crystalcompound having positive Δ∈ has a —CF₂O structure, and the liquidcrystal compound having neutral Δ∈ has an alkenyl group. Thesecharacteristics are widely known in the field of liquid crystalcompositions (Patent Literatures 1 to 4).

On the other hand, with expanding application of liquid crystal displaydevices, significant changes are found in use method and manufacturingmethod thereof. In order to cope with these changes, it is demanded tooptimize characteristics other than basic physical property values whichhave been known. That is, VA-mode and IPS-mode liquid crystal displaydevices using liquid crystal compositions are widely used, andsupersized liquid crystal devices of 50 inches or more are put intopractical application. With increases in substrate size, instead of ausual vacuum injection method, a one drop fill (ODF) method becomes themainstream of a method of injecting a liquid crystal composition into asubstrate. However, when a liquid crystal composition is dropped on asubstrate, the problem of degrading display quality by dropping marks issurfaced. Further, in a process of manufacturing a liquid crystaldisplay device by the ODF method, it is necessary to drop a liquidcrystal in an optimum amount according to the size of a liquid crystaldisplay device. A large deviation of the dropping amount from theoptimum value disrupts a balance between previously designed refractiveindex and driving electric field of a liquid crystal display device andcauses the occurrence of spots and display defects such as contrastdefect and the like. In particular, small liquid crystal display devicesin heavy use for recently popular smart phones have a small optimumamount of liquid crystal filling, and thus it is difficult to control adeviation from the optimum value within a predetermined range.Therefore, in order to maintain liquid crystal display devices in highyield, for example, a liquid crystal composition is required to belittle influenced by a rapid pressure change and impact produced in adropping apparatus during dropping of a liquid crystal, and to becapable of continuous stable dropping over a long time.

Accordingly, for liquid crystal compositions used for active matrixdrive liquid crystal display devices which are driven with TFT elementsor the like, developments are being required in view of a method formanufacturing a liquid crystal display device in addition to thecharacteristic of having high resistivity, high voltage holding ratio,and stability to external stimuli such as light, heat, and the like,which has been regarded as important, while maintaining thecharacteristics and performance, such as fast response and the like,which are required for liquid crystal display devices.

CITATION LIST Patent Literature

PTL 1: Japanese Unexamined Patent Application Publication No.2008-037918

PTL 2: Japanese Unexamined Patent Application Publication No.2008-038018

PTL 3: Japanese Unexamined Patent Application Publication No.2010-275390

PTL 4: Japanese Unexamined Patent Application Publication No.2011-052120

SUMMARY OF INVENTION Technical Problem

A problem to be solved by the invention is to provide a liquid crystalcomposition having positive Δ∈, a liquid phase over a wide temperaturerange, low viscosity, good solubility at a low temperature, highresistivity and voltage holding ratio, and stability to heat and light,and being capable of producing, in high yield, a liquid crystal displaydevice having good display quality and causing little display defectssuch as image sticking, dropping marks, and the like, and also provide aliquid crystal display device using the liquid crystal composition.

Solution to Problem

As a result of research on various liquid crystal compounds and variouschemical substances, the inventors of the present invention found thatthe problem can be resolved by combining specified liquid crystalcompounds, leading to the achievement of the present invention. That is,a first embodiment of the present invention relates to a liquid crystalcomposition described below, a second embodiment of the presentinvention relates to a liquid crystal device described below, and athird embodiment of the present invention relates to a liquid crystaldisplay described below.

[1] A liquid crystal composition containing any one or two or more ofcompounds represented by general formula (i) below and any one or two ormore of compounds represented by general formula (ii) below.

(In the formulae, R^(11a) and R^(21a) each independently represent analkyl group having 1 to 8 carbon atoms; one or nonadjacent two or more—CH₂— in the alkyl group may be each independently substituted by—CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—; one or two or more hydrogenatoms in the alkyl group may be each independently substituted by afluorine atom or a chlorine atom; m¹¹ represents 1 or 2; A¹¹ representsa trans-1,4-cyclohexylene group or a 1,4-phenylene group which may havea fluorine atom or a chlorine atom substituted for a hydrogen atom; whenm¹¹ is 1, A¹¹ represents a 1,4-phenylene group which may have a fluorineatom or a chlorine atom substituted for a hydrogen atom; when m¹¹ is 2,a plurality of A¹¹ may be the same or different, and at least one A¹¹represents a 1,4-phenylene group which may have a fluorine atom or achlorine atom substituted for a hydrogen atom;

X¹¹ represents a hydrogen atom, a fluorine atom, or a chlorine atom; X¹²represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyanogroup, —CF₃, or —OCF₃; m²¹ represents 0 or 1; X²¹, X²², X²³, and X²⁴each independently represent a hydrogen atom, a fluorine atom, or achlorine atom; and X²⁵ represents a hydrogen atom, a fluorine atom, achlorine atom, a cyano group, —CF₃, or —OCF₃.)

[2] The liquid crystal composition described above in [1], wherein m¹¹in the general formula (i) is 2.

[3] The liquid crystal composition described above in [1] or [2],containing two or more compounds represented by the general formula (i).

[4] The liquid crystal composition described above in any one of [1] to[3], containing two or more compounds represented by the general formula(ii).

[5] The liquid crystal composition described above in any one of [1] to[4], containing a compound represented by general formula (L) below.

(In the formula, R^(L1) and R^(L2) each independently represents analkyl group having 1 to 8 carbon atoms; one or nonadjacent two or more—CH₂— in the alkyl group may be each independently substituted by—CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—;

OL represents 0, 1, 2, or 3;

B^(L1), B^(L2), and B^(L3) each independently represent a group selectedfrom the group consisting of:

(a) a 1,4-cyclohexylene group (one —CH₂— or nonadjacent two or more—CH₂— present in the group may be substituted by —O—); and

(b) a 1,4-phenylene group (one —CH═ or nonadjacent two or more —CH═present in the group may be substituted by —N═), and one and/or two ormore hydrogen atoms in the group (a) and the group (b) may be eachindependently substituted by a cyano group, a fluorine atom, or achlorine atom;

L^(L1) and L^(L2) each independently represent —CH₂CH₂—, —(CH₂)₄—,—OCH₂—, —CH₂O—, —COO—, —OCO—, —OCF₂—, —CF₂O—, —CH═N—N═CH—, —CH═CH—,—CF═CF—, or —C≡C—; and

when OL is 2 or 3, and a plurality of L^(L2) are present, L^(L2) may bethe same or different, and when OL is 2 or 3, and a plurality of B^(L3)are present, B^(L3) may be the same or different.)

[6] The liquid crystal composition described above in any one of [1] to[5], containing a compound represented by general formula (M) below.

(In the formula, R^(M1) represent an alkyl group having 1 to 8 carbonatoms; one or nonadjacent two or more —CH₂— in the alkyl group may beeach independently substituted by —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or—OCO—;

PM represents 0, 1, 2, 3, or 4;

C^(M1) and C^(M2) each independently represent a group selected from thegroup consisting of:

(d) a 1,4-cyclohexylene group (one —CH₂— or nonadjacent two or more—CH₂— present in the group may be substituted by —O— or —S—); and

(e) a 1,4-phenylene group (one —CH═ or nonadjacent two or more —CH═present in the group may be substituted by —N═), and one and/or two ormore hydrogen atoms in the group (d) and the group (e) may be eachindependently substituted by a cyano group, a fluorine atom, or achlorine atom;

K^(M1) and K^(M2) each independently represent a single bond, —CH₂CH₂—,—(CH₂)₄—, —OCH₂—, —CH₂O—, —OCF₂—, —CF₂O—, —COO—, —OCO—, or —C≡C—;

when PM is 2, 3, or 4, and a plurality of K^(M1) are present, K^(M1) maybe the same or different, and when PM is 2, 3, or 4, and a plurality ofC^(M2) are present, C^(M2) may be the same or different;

X^(M1) and X^(M3) each independently represent a hydrogen atom, achlorine atom, or a fluorine atom; and

X^(M2) represents a hydrogen atom, a fluorine atom, a chlorine atom, acyano group, a trifluoromethyl group, a fluoromethoxy group, adifluoromethoxy group, a trifluoromethoxy group, or a2,2,2-trifluoroethyl group. However, the compounds represented by thegeneral formula (i) and general formula (ii) are excluded.)

[7] A liquid crystal display device using the liquid crystal compositiondescribed above in any one of [1] to [6].

[8] A liquid crystal display device for an IPS mode using the liquidcrystal composition described above in any one of [1] to [6].

[9] A liquid crystal display device for a FFS mode using the liquidcrystal composition described above in any one of [1] to [6].

[10] A liquid crystal display device for an OCB mode using the liquidcrystal composition described above in any one of [1] to [6].

[11] A liquid crystal display device for an ECB mode using the liquidcrystal composition described above in any one of [1] to [6].

[12] A liquid crystal display device for a VA mode using the liquidcrystal composition described above in any one of [1] to [6].

[13] A liquid crystal display using the liquid crystal display devicedescribed above in any one of [7] to [12].

Advantageous Effects of Invention

A liquid crystal composition having positive dielectric anisotropyaccording to the present invention has a liquid phase over a widetemperature range, significantly lower viscosity than usual, goodsolubility at a low temperature, and very small changes in resistivityand voltage holding ratio with heat and light. Therefore, the liquidcrystal composition of the present invention has high practicability(applicability) for liquid crystal products, and an IPS-mode or FFS-modeliquid crystal display device using the liquid crystal composition canachieve fast response. Also, the liquid crystal composition of thepresent invention is very useful because it can stably exhibit itsperformance even after a process for manufacturing a liquid crystaldisplay device, and thus display defects due to the manufacturingprocess are suppressed, thereby permitting manufacture of a liquidcrystal display device in high yield.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional view of a liquid crystal display device of thepresent invention. A substrate denoted by 100 to 105 is referred to as a“back plane”, and a substrate denoted by 200 to 205 is referred to as a“front plane”.

FIG. 2 is a drawing of an exposure step using, as a photomask pattern, apattern for forming columnar spacers on a black matrix.

DESCRIPTION OF EMBODIMENTS

A liquid crystal composition having positive dielectric anisotropyaccording to a first embodiment of the present invention contains acomponent (A) which is a dielectrically positive component. Thecomponent (A) is composed of a compound having a dielectric anisotropyof 2 or more. The dielectric anisotropy of a compound refers to a valueobtained by extrapolation from a measured value of dielectric anisotropyof a composition prepared by adding the compound to a composition whichhas a dielectric anisotropy of about 0 at 25° C.

In a composition below, “%” represents “% by mass” unless otherwisespecified.

The component (A) contains any one or two or more of compoundsrepresented by general formula (i) below and any one or two or more ofcompounds represented by general formula (ii) below.

<Compound Represented by General Formula (i)>

In the general formula (i), R^(11a) represents an alkyl group having 1to 8 carbon atoms, one or nonadjacent two or more —CH₂— in the alkylgroup may be each independently substituted by —CH═CH—, —C≡C—, —O—,—CO—, —COO—, or —OCO—, and one or two or more hydrogen atoms in thealkyl group may be substituted by a fluorine atom or a chlorine atom.

Further, R^(11a) is preferably a linear alkyl group having 1 to 8 carbonatoms, and the number of carbon atoms in the alkyl group is preferably 1to 6, more preferably 2 to 5, even more preferably 2, 3, or 5, even morepreferably 2 or 3, and still more preferably 3.

In the general formula (i), X¹¹ is preferably a hydrogen atom or afluorine atom.

In the general formula (i), X¹² is preferably a fluorine atom or —OCF₃.

When m¹¹ in the general formula (i) is 2, a plurality of A¹¹ may be thesame or different.

When m¹¹ in the general formula (i) is 1, A¹¹ is preferably a1,4-phenylene group which may be substituted by a fluorine atom; whenm¹¹ is 2, at least one of the two A¹¹ is preferably a 1,4-phenylenegroup which may be substituted by a fluorine atom; and when m¹¹ is 2,one of the A¹¹ is a trans-1,4-cyclohexylene group, and the other A¹¹ isa 1,4-phenylene group which may be substituted by a fluorine atom, thetrans-1,4-cyclohexylene group as one of the A¹¹ is preferably bonded toa cyclohexylene group having the alkyl group to form linkage of twocyclohexylene groups.

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(i) can be used in combination according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used andrepresented by the general formula (i) is 1. According to anotherembodiment of the present invention, the number of the types is 2 ormore, and when a plurality of compounds are used, two compounds arepreferably used. In this case, it is preferred to use a compound havinga fluorine atom as X¹² and a compound having —OCF₃ as X¹².

In view of solubility at a low temperature, transition temperature,electric reliability, birefringence, etc., the content of a compoundrepresented by the general formula (i) has a preferred upper limit valueand lower limit value according to an embodiment.

Relative to the total mass of the liquid crystal composition of thepresent invention, the lower limit value of the content of the compoundis preferably 1%, preferably 5%, preferably 7%, and preferably 9%, andthe upper limit value of the content of the compound is preferably 25%,preferably 20%, preferably 16%, preferably 12%, preferably 10%,preferably 8%, and preferably 7%.

When only one of the compounds is used, the lower limit value of thecontent of the compound relative to the total mass is preferably 1%,preferably 2%, preferably 5%, and preferably 6%, and the upper limitvalue of the content of the compound relative to the total mass ispreferably 25%, preferably 20%, preferably 15%, preferably 12%,preferably 10%, preferably 9%, and preferably 7%.

When two or more of the compounds are used, the lower limit value of thetotal content of the two compounds relative to the total mass ispreferably 6%, preferably 8%, and preferably 10%, and the upper limitvalue of the total content of the two compounds relative to the totalmass is preferably 25%, preferably 20%, preferably 15%, and preferably12%.

When solubility of the liquid crystal composition is regarded asimportant, two compounds represented by the general formula (i) arepreferably used, and when the content of compounds represented by thegeneral formula (i) is desired to be increased, the two compounds arepreferably used.

According to an embodiment, the content of a compound represented by thegeneral formula (i) relative to the total mass is preferably 1% to 15%by mass, preferably 1% to 12% by mass, preferably 1% to 10% by mass, andpreferably 1% to 9% by mass, and according to another embodiment, thecontent is preferably 5% to 25% by mass, preferably 5% to 20% by mass,preferably 7% to 15% by mass, and preferably 7% to 13% by mass.

In the general formula (i), m¹¹ is preferably 1 or 2, and when fastresponse is regarded as important, m¹¹ is preferably 1, while when Tniis regarded as important, m¹¹ is preferably 2.

A compound in which m¹¹ in the general formula (i) is 2 is preferably acompound represented by general formula (X-1) below.

(In the formula, X¹⁰¹ to X¹⁰³ each independently represent a fluorineatom or a hydrogen atom, and R¹⁰ represents an alkyl group having 1 to 5carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxygroup having 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-1) can beproperly combined according to each embodiment in view of solubility ata low temperature, transition temperature, electric reliability,birefringence, etc. For example, according to an embodiment of thepresent invention, the number of the compound used is 1. According toanother embodiment of the present invention, the number of the compoundsis 2. According to still another embodiment, the number of the compoundsis 3. According to a further embodiment, the number of the compounds is4. According to a further embodiment, the number of the compounds is 5or more.

In view of solubility at a low temperature, transition temperature,electric reliability, birefringence, etc., the content of a compoundrepresented by the general formula (X-1) has an upper limit value and alower limit value according to each embodiment. For example, accordingto an embodiment of the present invention, the content of the compoundrelative to the total mass of the liquid crystal composition of thepresent invention is 2% to 40% by mass; according to another embodiment,the content of the compound is 3% to 40% by mass; according to stillanother embodiment, the content of the compound is 5% to 40% by mass;according to a further embodiment, the content of the compound is 6% to40% by mass; according to a further embodiment, the content of thecompound is 7% to 40% by mass; according to a further embodiment, thecontent of the compound is 8% to 40% by mass; according to a furtherembodiment, the content of the compound is 9% to 40% by mass; accordingto a further embodiment, the content of the compound is 13% to 40% bymass; according to a further embodiment, the content of the compound is18% to 40% by mass; and according to a further embodiment, the contentof the compound is 23% to 40% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 2% to 40% bymass; according to another embodiment, the content of the compound is 2%to 30% by mass; according to still another embodiment, the content ofthe compound is 2% to 25% by mass; according to a further embodiment,the content of the compound is 2% to 20% by mass; according to a furtherembodiment, the content of the compound is 2% to 15% by mass; accordingto a further embodiment, the content of the compound is 2% to 10% bymass; according to a further embodiment, the content of the compound is2% to 6% by mass; and according to a further embodiment, the content ofthe compound is 2% to 4% by mass.

Further, the compound represented by the general formula (X-1) and usedin the liquid crystal composition of the present invention is preferablya compound represented by general formula (X-1-1).

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-1-1) can beproperly combined according to each embodiment in view of solubility ata low temperature, transition temperature, electric reliability,birefringence, etc. For example, according to an embodiment of thepresent invention, the number of the compound used is 1. According toanother embodiment of the present invention, the number of the compoundsis 2. According to still another embodiment of the present invention,the number of the compounds is 3. According to a further embodiment ofthe present invention, the number of the compounds is 4 or more.

The content of a compound represented by the general formula (X-1-1) hasan upper limit value and a lower limit value according to eachembodiment in view of solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc. For example,according to an embodiment of the present invention, the content of thecompound relative to the total mass of the liquid crystal composition ofthe present invention is 3% to 30% by mass; according to anotherembodiment, the content of the compound is 4% to 30% by mass; accordingto still another embodiment, the content of the compound is 6% to 30% bymass; according to a further embodiment, the content of the compound is9% to 30% by mass; according to a further embodiment, the content of thecompound is 12% to 30% by mass; according to a further embodiment, thecontent of the compound is 15% to 30% by mass; according to a furtherembodiment, the content of the compound is 18% to 30% by mass; andaccording to a further embodiment, the content of the compound is 21% to30% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 3% to 30% bymass; according to another embodiment, the content of the compound is 3%to 20% by mass; according to still another embodiment, the content ofthe compound is 3% to 13% by mass; according to a further embodiment,the content of the compound is 3% to 10% by mass; and according to afurther embodiment, the content of the compound is 3% to 7% by mass.

Further, preferred examples of the compound represented by the generalformula (X-1-1) and used in the liquid crystal composition of thepresent invention include compounds represented by formula (36.1) toformula (36.4), and particularly a compound represented by formula(36.1) and/or formula (36.2) is preferably contained.

A compound in which m¹¹ in the general formula (i) is 2 is preferably acompound represented by general formula (X-1-2) below.

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Relative to the total mass of the liquid crystal composition of thepresent invention, the content of a compound represented by the generalformula (X-1-2) is preferably 1% by mass or more, more preferably 2% bymass or more, and still more preferably 6% by mass or more. In addition,in view of solubility at a low temperature, transition temperature,electric reliability, etc., the maximum ratio is preferably limited to15% by mass or less, more preferably 13% by mass or less, still morepreferably 10% by mass or less, and particularly preferably 9% by massor less.

Examples of a more preferred embodiment include embodiments where thecontent is 1% to 10% by mass, 2% to 8% by mass, 2% to 7% by mass, 2% to5% by mass, 4% to 8% by mass, and 5% to 8% by mass, respectively.

Preferred examples of the compound represented by the general formula(X-1-2) include compounds represented by formula (37.1) to formula(37.4), and particularly a compound represented by formula (37.2) ispreferably contained.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of a compound represented by the formula(37.2) relative to the total mass of the liquid crystal composition ofthe present invention is preferably 1% by mass or more and 20% by massor less, more preferably 2% by mass or more and 15% by mass or less,still more preferably 2% by mass or more and 10% by mass or less, andparticularly preferably 2% by mass or more and 8% by mass or less.

A compound in which m¹¹ in the general formula (i) is 2 is preferably acompound represented by general formula (X-1-3) below.

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, butcompounds represented by the general formula (X-1-3) are preferably usedalone or in combination of two or more in view of solubility at a lowtemperature, transition temperature, electric reliability,birefringence, etc.

Relative to the total mass of the liquid crystal composition of thepresent invention, the content of a compound represented by the generalformula (X-1-3) is preferably 1% by mass or more, more preferably 2% bymass or more, and still more preferably 3% by mass or more. In addition,in view of solubility at a low temperature, transition temperature,electric reliability, etc., the maximum ratio is preferably limited to15% by mass or less, more preferably 10% by mass or less, still morepreferably 8% by mass or less, and particularly preferably 7% by mass orless.

Examples of q more preferred embodiment include embodiments where thecontent is 1% to 10% by mass, 3% to 8% by mass, 2% to 6% by mass, 2% to5% by mass, 2% to 4% by mass, 3% to 7% by mass, 4% to 7% by mass, and 5%to 7% by mass, respectively.

Preferred examples of the compound represented by the general formula(X-1-3) include compounds represented by formula (38.1) to formula(38.4), and particularly a compound represented by formula (38.2) ispreferably contained.

In the liquid crystal composition of the present invention, the contentof the compound represented by the formula (38.2) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 1% by mass or more and 15% by mass or less, more preferably2% by mass or more and 10% by mass or less, still more preferably 3% bymass or more and 8% by mass or less, and particularly preferably 4% bymass or more and 6% by mass or less.

A compound in which m¹¹ in the general formula (i) is 2 is preferably acompound represented by general formula (X-2) below.

(In the formula, X¹⁰² and X¹⁰³ each independently represent a fluorineatom or a hydrogen atom, Y¹⁰ represents a fluorine atom, a chlorineatom, or —OCF₃, and R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-2) arepreferably used alone or in combination of two or more in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

A compound in which m¹¹ in the general formula (i) is 2 is preferably acompound represented by general formula (X-2-1) below.

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, butcompounds represented by the general formula (X-2-1) are preferably usedalone or in combination of two or more and more preferably used alone orin combination of three or more in view of solubility at a lowtemperature, transition temperature, electric reliability,birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (X-2-1) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 3% by mass or moreand 15% by mass or less, more preferably 4% by mass or more and 10% bymass or less, and particularly preferably 4% by mass or more and 7% bymass or less.

Preferred examples of the compound represented by the general formula(X-2-1) include compounds represented by formula (39.1) to formula(39.4), and particularly a compound represented by formula (39.2) ispreferably contained.

In the liquid crystal composition of the present invention, the contentof a compound represented by the formula (39.2) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 2% by mass or more and 15% by mass or less, more preferably3% by mass or more and 15% by mass or less, even more preferably 3% bymass or more and 10% by mass or less, still more preferably 4% by massor more and 8% by mass or less, and particularly preferably 4% by massor more and 7% by mass or less.

Within the particularly preferred range, the content may be 4 to 6% bymass, 4 to 5% by mass, 5 to 7% by mass, or 6 to 7% by mass.

A compound in which m¹¹ in the general formula (i) is 2 is preferably acompound represented by general formula (X-2-2) below.

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-2-2) arepreferably used alone or in combination of two or more in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (X-2-2) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 3% by mass or moreand 20% by mass or less, more preferably 6% by mass or more and 16% bymass or less, still more preferably 9% by mass or more and 12% by massor less, and particularly preferably 9% by mass or more and 10% by massor less.

Preferred examples of the compound represented by the general formula(X-2-2) include compounds represented by formula (40.1) to formula(40.4), and particularly a compound represented by formula (40.2) ispreferably contained.

A compound in which m¹¹ in the general formula (i) is 1 is preferably acompound represented by general formula (XIV-2-2) below.

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (XIV-2-2) relative to the total mass of the liquidcrystal composition of the present invention is preferably 1% by mass ormore and 20% by mass or less, more preferably 1% by mass or more and 15%by mass or less, still more preferably 2% by mass or more and 10% bymass or less, and particularly preferably 3% by mass or more and 7% bymass or less.

Preferred examples of the compound represented by the general formula(XIV-2-2) include compounds represented by formula (54.1) to formula(54.4), and particularly a compound represented by formula (54.2) and/orformula (54.4) is preferably contained.

In the liquid crystal composition of the present invention, the contentof a compound represented by the formula (54.2) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 1% by mass or more and 35% by mass or less, more preferably1% by mass or more and 25% by mass or less, even more preferably 1% bymass or more and 20% by mass or less, even more preferably 1% by mass ormore and 15% by mass or less, still more preferably 1% by mass or moreand 10% by mass or less, still more preferably 2% by mass or more and 8%by mass or less, and particularly preferably 3% by mass or more and 7%by mass or less.

Within the particularly preferred range, the content may be 3 to 5% bymass or 5 to 7% by mass.

When two compounds represented by the general formula (i) are used, acombination of compounds represented by the formula (37.2) and theformula (39.2) and a combination of compounds represented by the formula(38.2) and the formula (39.2) are preferred.

A compound in which m¹¹ in the general formula (i) is 1 is preferably acompound represented by general formula (XIV-2-3) below.

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (XIV-2-3) relative to the total mass of the liquidcrystal composition of the present invention is preferably 5% by mass ormore and 30% by mass or less, more preferably 9% by mass or more and 27%by mass or less, still more preferably 12% by mass or more and 24% bymass or less, and particularly preferably 12% by mass or more and 20% bymass or less.

Preferred examples of the compound represented by the general formula(XIV-2-3) include compounds represented by formula (55.1) to formula(55.4), and particularly a compound represented by formula (55.2) and/orformula (55.4) is preferably contained.

A compound in which m¹¹ in the general formula (i) is 1 is preferably acompound represented by general formula (XIV-2-4) below.

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not limited, but a plurality ofcompounds represented by the general formula (XIV-2-4) can be properlycombined according to each embodiment in view of solubility at a lowtemperature, transition temperature, electric reliability,birefringence, etc. For example, according to an embodiment of thepresent invention, the number of the compound used is 1. According toanother embodiment of the present invention, the number of the compoundsis 2. According to a further embodiment of the present invention, thenumber of the compounds is 3 or more.

The content of a compound represented by the general formula (XIV-2-4)has an upper limit value and a lower limit value according to eachembodiment in view of solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 35% by mass; according toanother embodiment, the content of the compound is 5% to 35% by mass;according to still another embodiment, the content of the compound is 8%to 35% by mass; according to a further embodiment, the content of thecompound is 9% to 35% by mass; according to a further embodiment, thecontent of the compound is 10% to 35% by mass; according to a furtherembodiment, the content of the compound is 18% to 35% by mass; accordingto a further embodiment, the content of the compound is 21% to 35% bymass; according to a further embodiment, the content of the compound is22% to 35% by mass; and according to a further embodiment, the contentof the compound is 24% to 35% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 2% to 35% bymass; according to another embodiment, the content of the compound is 2%to 30% by mass; according to still another embodiment, the content ofthe compound is 2% to 25% by mass; according to a further embodiment,the content of the compound is 2% to 20% by mass; according to a furtherembodiment, the content of the compound is 2% to 15% by mass; andaccording to a further embodiment, the content of the compound is 2% to10% by mass.

When the liquid crystal composition of the present invention is used fora liquid crystal display device having a low drive voltage, it isdesired to slightly increase the content of the compound represented bythe general formula (XIV-2-4). When the liquid crystal composition isused for a liquid crystal display device having fast response, it isdesired to slightly decrease the content of the compound represented bythe general formula (XIV-2-4).

Further, preferred examples of the compound represented by the generalformula (XIV-2-4) include compounds represented by formula (56.1) toformula (56.4), and particularly a compound represented by formula(56.1), formula (56.2), and/or formula (56.4) is preferably contained.

A compound in which m¹¹ in the general formula (i) is 1 is preferably acompound represented by general formula (XIV-2-5) below.

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (XIV-2-5) relative to the total mass of the liquidcrystal composition of the present invention is preferably 5% by mass ormore and 25% by mass or less, more preferably 10% by mass or more and22% by mass or less, still more preferably 13% by mass or more and 18%by mass or less, and particularly preferably 13% by mass or more and 15%by mass or less.

Further, preferred examples of the compound represented by the generalformula (XIV-2-5) include compounds represented by formula (57.1) toformula (57.4), and particularly a compound represented by formula(57.1) is preferably contained.

A compound in which m¹¹ in the general formula (i) is 1 is preferably acompound represented by general formula (XIV-2-6) below.

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (XIV-2-6) relative to the total mass of the liquidcrystal composition of the present invention is preferably 5% by mass ormore and 25% by mass or less, more preferably 10% by mass or more and22% by mass or less, still more preferably 15% by mass or more and 20%by mass or less, and particularly preferably 15% by mass or more and 17%by mass or less.

Further, preferred examples of the compound represented by the generalformula (XIV-2-6) include compounds represented by formula (58.1) toformula (58.4), and particularly a compound represented by formula(58.2) is preferably contained.

<Compound Represented by General Formula (ii)>

In the general formula (ii), R^(21a) represents a linear alkyl grouphaving 1 to 8 carbon atoms, and the number of carbon atoms is preferably1 to 6, more preferably 2 to 5, and still more preferably 2 to 3.

In the general formula (ii), m²¹ represents 0 or 1, and X²¹, X²², X²³,and X²⁴ each independently represent a hydrogen atom, a fluorine atom,or a chlorine atom, and X²⁵ represents a hydrogen atom, a fluorine atom,a chlorine atom, a cyano group, —CF₃, or —OCF₃.

In addition, m²¹ is preferably 1.

When m²¹ is 1, at least one of X²¹ and X²² is preferably a hydrogenatom, and both of X²¹ and X²² are more preferably hydrogen atoms.

X²³, X²⁴, and X²⁵ are preferably each independently a fluorine atom, atleast two of X²³, X²⁴, and X²⁵ are more preferably fluorine atoms, andall of X²³, X²⁴, and X²⁵ are still more preferably fluorine atoms.

In addition, at least two of X²¹ to X²⁴ are preferably fluorine atoms.

The compound represented by the general formula (ii) is preferably acompound represented by general formula (X-6) below.

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, butcompounds represented by the general formula (X-6) are preferably aloneor in combination of two or more in view of solubility at a lowtemperature, transition temperature, electric reliability,birefringence, etc.

The content of a compound represented by the general formula (ii) has anupper limit value and lower limit value according to each embodiment inview of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc.

When only one of the compounds is used, the lower limit value of thecontent of the compound relative to the total mass is preferably 1%,more preferably 2%, and still more preferably 3%, and the upper limitvalue of the content of the compound relative to the total mass ispreferably 15%, more preferably 12%, still more preferably 10%,particularly preferably 8%, and most preferably 7%.

When two of the compounds are used, the lower limit value of the totalcontent of the two compounds relative to the total mass is preferably4%, more preferably 5%, and still more preferably 6%, and the upperlimit value of the total content of the two compounds relative to thetotal mass is preferably 25%, more preferably 20%, even more preferably18%, and still more preferably 16%.

When solubility of the liquid crystal composition is regarded asimportant, two compounds represented by the general formula (ii) arepreferably used, and when the content of compounds represented by thegeneral formula (ii) is desired to be increased, the two compounds arepreferably used.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 30% by mass; according toanother embodiment, the content of the compound is 3% to 25% by mass;according to still another embodiment, the content of the compound is 3%to 10% by mass; according to a further embodiment, the content of thecompound is 3% to 7% by mass; according to a further embodiment, thecontent of the compound is 5% to 10% by mass; according to a furtherembodiment, the content of the compound is 6% to 16% by mass; andaccording to a further embodiment, the content of the compound is 14% to20% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass of the liquidcrystal composition of the present invention is 1% to 30% by mass;according to another embodiment, the content of the compound is 1% to20% by mass; according to still another embodiment, the content of thecompound is 1% to 13% by mass; according to a further embodiment, thecontent of the compound is 1% to 10% by mass; according to a furtherembodiment, the content of the compound is 1% to 7% by mass; andaccording to a further embodiment, the content of the compound is 1% to3% by mass.

Further, preferred examples of the compound represented by the generalformula (X-6) include compounds represented by formula (44.1) to formula(44.4), and particularly a compound represented by formula (44.1) and/orformula (44.2) is preferably contained.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of a compound represented by the formula(44.1) relative to the total mass of the liquid crystal composition ofthe present invention is preferably 1% by mass or more and 25% by massor less, more preferably 3% by mass or more and 20% by mass or less,still more preferably 3% by mass or more and 15% by mass or less,particularly more preferably 3% by mass or more and 10% by mass or less,and most preferably 3% by mass or more and 8% by mass or less.

Within the most preferred range, the content may be, for example, 3% bymass or more and 6% by mass or less, 3% by mass or more and 4% by massor less, 4% by mass or more and 8% by mass or less, 6% by mass or moreand 8% by mass or less, or 7% by mass or more and 8% by mass or less.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of a compound represented by the formula(44.2) relative to the total mass of the liquid crystal composition ofthe present invention is preferably 1% by mass or more and 25% by massor less, more preferably 3% by mass or more and 20% by mass or less,still more preferably 3% by mass or more and 15% by mass or less,particularly more preferably 3% by mass or more and 10% by mass or less,and most preferably 3% by mass or more and 8% by mass or less.

Within the most preferred range, the content may be, for example, 3% bymass or more and 6% by mass or less, 3% by mass or more and 4% by massor less, 4% by mass or more and 8% by mass or less, 6% by mass or moreand 8% by mass or less, or 7% by mass or more and 8% by mass or less.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the total content of the compound represented by theformula (44.1) and a compound represented by the formula (44.2) relativeto the total mass of the liquid crystal composition of the presentinvention is preferably 5% by mass or more and 45% by mass or less, morepreferably 5% by mass or more and 25% by mass or less, still morepreferably 6% by mass or more and 20% by mass or less, and particularlypreferably 6% by mass or more and 16% by mass or less.

Within the particularly preferred range, the content may be, forexample, 6% by mass or more and 15% by mass or less, 6% by mass or moreand 12% by mass or less, 6% by mass or more and 10% by mass or less, 6%by mass or more and 8% by mass or less, 8% by mass or more and 16% bymass or less, 10% by mass or more and 16% by mass or less, 12% by massor more and 16% by mass or less, or 15% by mass or more and 16% by massor less.

Compounds represented by the general formula (i) and compoundsrepresented by the general formula (ii) are preferably used incombination of two to four and more preferably used in combination ofthree or four in total.

The lower limit value of the total content of compounds represented bythe general formula (i) and compounds represented by the general formula(ii) relative to the total mass of the liquid crystal composition of thepresent invention is preferably 4%, more preferably 6%, still morepreferably 8%, and particularly preferably 10%. The upper limit value ofthe total content relative to the total mass is preferably 40%, morepreferably 35%, still more preferably 30%, particularly preferably 27%,and most preferably 20%.

When one compound represented by the general formula (i) and onecompound represented by the general formula (ii), i.e., two compounds intotal, are used, the lower limit value of the total content of twocompounds relative to the total mass is preferably 6%, more preferably8%, even more preferably 10%, and still more preferably 12%. The upperlimit value of the total content of two compounds relative to the totalmass is preferably 20%, more preferably 18%, still more preferably 16%,and particularly preferably 14%.

When one or two compounds represented by the general formula (i) and twoor one compound represented by the general formula (ii), i.e., threecompounds in total, are used, the lower limit value of the total contentof three compounds relative to the total mass is preferably 5%, morepreferably 8%, and still more preferably 10%. The upper limit value ofthe total content of three compounds relative to the total mass ispreferably 30%, more preferably 24%, still more preferably 21%, andparticularly preferably 18%.

When one to three compounds represented by the general formula (i) andone to three compounds represented by the general formula (ii), i.e.,four compounds in total, are used, the lower limit value of the totalcontent of four compounds relative to the total mass is preferably 15%,more preferably 17%, still more preferably 19%, particularly preferably20%, and most preferably 24%. The upper limit value of the total contentof four compounds relative to the total mass is preferably 40%, morepreferably 35%, still more preferably 30%, and particularly preferably27%.

When solubility of the liquid crystal composition is regarded asimportant, the above-described compounds are preferably used incombination of two to four in total.

Preferred combinations include a combination of compounds represented bythe formula (37.2) and the formula (44.2), a combination of compoundsrepresented by the formula (37.2), the formula (44.1), and the formula(44.2), a combination of compounds represented by the formula (37.2),the formula (39.2), the formula (44.1), and the formula (44.2), and acombination of compounds represented by the formula (38.2), the formula(39.2), the formula (44.1), and the formula (44.2).

The liquid crystal composition according to the first embodiment of thepresent invention can also contain any one or two or more of compoundsrepresented by general formula (L) below.

(In the formula, R^(L1) and R^(L2) each independently represent an alkylgroup having 1 to 8 carbon atoms; one or nonadjacent two or more —CH₂—in the alkyl group may be each independently substituted by —CH═CH—,—C≡C—, —O—, —CO—, —COO—, or —OCO—;

OL represents 0, 1, 2, or 3;

B^(L1), B^(L2), and B^(L3) each independently represent a group selectedfrom the group consisting of:

(a) a 1,4-cyclohexylene group (one —CH₂— or nonadjacent two or more—CH₂— in the group may be substituted by —O—); and

(b) a 1,4-phenylene group (one —CH═ or nonadjacent two or more —CH═ inthe group may be substituted by —N═), and one and/or two or morehydrogen atoms in the group (a) and the group (b) may be eachindependently substituted by a cyano group, a fluorine atom, or achlorine atom;

L^(L1) and L^(L2) each independently represent a single bond, —CH₂CH₂—,—(CH₂)₄—, —OCH₂—, —CH₂O—, —COO—, —OCO—, —OCF₂—, —CF₂O—, —CH═N—N═CH—,—CH═CH—, —CF═CF—, or —C≡C—; and

when OL is 2 or 3, and a plurality of L^(L2) are present, L^(L2) may bethe same or different, and when OL is 2 or 3, and a plurality of B^(L3)are present, B^(L3) may be the same or different.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(L) can be properly used in combination according to desired performancesuch as solubility at a low temperature, transition temperature,electric reliability, birefringence, etc. For example, according to anembodiment of the present invention, the number of the type of compoundused is 1. According to another embodiment of the present invention, thenumber of the types is 2. According to still another embodiment of thepresent invention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4.According to a further embodiment of the present invention, the numberof the types is 5. According to a further embodiment of the presentinvention, the number of the types is 6. According to a furtherembodiment of the present invention, the number of the types is 7.According to a further embodiment of the present invention, the numberof the types is 8. According to a further embodiment of the presentinvention, the number of the types is 9. According to a furtherembodiment of the present invention, the number of the types is 10 ormore.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (L) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 1% to 95% by mass. According toanother embodiment of the present invention, the content is 10% to 95%by mass. According to still another embodiment of the present invention,the content is 20% to 95% by mass. According to a further embodiment ofthe present invention, the content is 30% to 95% by mass. According to afurther embodiment of the present invention, the content is 40% to 95%by mass. According to a further embodiment of the present invention, thecontent is 50% to 95% by mass. According to a further embodiment of thepresent invention, the content is 55% to 95% by mass. According to afurther embodiment of the present invention, the content is 60% to 95%by mass. According to a further embodiment of the present invention, thecontent is 65% to 95% by mass. According to a further embodiment of thepresent invention, the content is 70% to 95% by mass. According to afurther embodiment of the present invention, the content is 75% to 95%by mass. According to a further embodiment of the present invention, thecontent is 80% to 95% by mass.

Further, for example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 1% to 95% bymass. According to another embodiment of the present invention, thecontent is 1% to 85% by mass. According to still another embodiment ofthe present invention, the content is 1% to 75% by mass. According to afurther embodiment of the present invention, the content is 1% to 65% bymass. According to a further embodiment of the present invention, thecontent is 1% to 55% by mass. According to a further embodiment of thepresent invention, the content is 1% to 45% by mass. According to afurther embodiment of the present invention, the content is 1% to 35% bymass. According to a further embodiment of the present invention, thecontent is 1% to 25% by mass.

When the viscosity of the liquid crystal composition of the presentinvention is kept low, and the liquid crystal composition having fastresponse is required, both the lower limit value and the upper limitvalue are preferably high. Further, when Tni of the liquid crystalcomposition of the present invention is kept high, and the liquidcrystal composition having good temperature stability is required, boththe lower limit value and the upper limit value are preferably high. Inaddition, when it is desired to increase dielectric anisotropy forkeeping the drive voltage low, both the lower limit value and the upperlimit value are preferably low.

When a ring structure to which each of R^(L1) and R^(L2) is bonded is aphenyl group (aromatic), R^(L1) and R^(L2) are each preferably a linearalkyl group having 1 to 5 carbon atoms, a linear alkoxy group having 1to 4 (or more) carbon atoms, or an alkenyl group having 4 to 5 carbonatoms, while when a ring structure to which each of R^(L1) and R^(L2) isbonded is a saturated ring structure, such as cyclohexane, pyran, ordioxane, R^(L1) and R^(L2) are each preferably a linear alkyl grouphaving 1 to 5 carbon atoms, a linear alkoxy group having 1 to 4 (ormore) carbon atoms, or a linear alkenyl group having 2 to 5 carbonatoms.

When the liquid crystal composition is required to have chemicalstability, a compound represented by the general formula (L) preferablydoes not contain a chlorine atom in its molecule.

The compound represented by the general formula (L) is preferably, forexample, a compound selected from a compound group represented bygeneral formula (I).

[Chem. 31]

R¹¹-A¹¹-A¹²-R¹²  (I)

(In the formula, R¹¹ and R¹² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms,or an alkenyl group having 2 to 5 carbon atoms, and A¹¹ and A¹² eachindependently represent a 1,4-cyclohexylene group, a 1,4-phenylenegroup, a 2-fluoro-1,4-phenylene group, or a 3-fluoro-1,4-phenylenegroup.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(I) can be properly used in combination according to desired performancesuch as solubility at a low temperature, transition temperature,electric reliability, birefringence, etc. For example, according to anembodiment of the present invention, the number of the type of compoundused is 1. According to another embodiment of the present invention, thenumber of the types is 2. According to still another embodiment of thepresent invention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4.According to a further embodiment of the present invention, the numberof the types is 5. According to a further embodiment of the presentinvention, the number of the types is 6 or more.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of a compound represented bythe general formula (I) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 75% by mass. According toanother embodiment of the present invention, the content is 15% to 75%by mass. According to still another embodiment of the present invention,the content is 18% to 75% by mass. According to a further embodiment ofthe present invention, the content is 20% to 75% by mass. According to afurther embodiment of the present invention, the content is 29% to 75%by mass. According to a further embodiment of the present invention, thecontent is 35% to 75% by mass. According to a further embodiment of thepresent invention, the content is 42% to 75% by mass. According to afurther embodiment of the present invention, the content is 47% to 75%by mass. According to a further embodiment of the present invention, thecontent is 53% to 75% by mass. According to a further embodiment of thepresent invention, the content is 56% to 75% by mass. According to afurther embodiment of the present invention, the content is 60% to 75%by mass. According to a further embodiment of the present invention, thecontent is 65% to 75% by mass.

Further, for example, according to an embodiment of the presentinvention, the content relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 75% by mass. According toanother embodiment of the present invention, the content is 3% to 65% bymass. According to still another embodiment of the present invention,the content is 3% to 55% by mass. According to a further embodiment ofthe present invention, the content is 3% to 50% by mass. According to afurther embodiment of the present invention, the content is 3% to 45% bymass. According to a further embodiment of the present invention, thecontent is 3% to 40% by mass. According to a further embodiment of thepresent invention, the content is 3% to 35% by mass. According to afurther embodiment of the present invention, the content is 3% to 30% bymass.

When the viscosity of the liquid crystal composition of the presentinvention is kept low, and the liquid crystal composition having fastresponse is required, both the lower limit value and the upper limitvalue are preferably high. Further, when Tni of the liquid crystalcomposition of the present invention is kept high, and the liquidcrystal composition having good temperature stability is required, boththe lower limit value and the upper limit value are preferably medium.In addition, when it is desired to increase dielectric anisotropy forkeeping the drive voltage low, both the lower limit value and the upperlimit value are preferably low.

When a ring structure to which R^(M1) is bonded is a phenyl group(aromatic), R^(M1) is preferably a linear alkyl group having 1 to 5carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms, or analkenyl group having 4 to 5 carbon atoms, while when a ring structure towhich R^(M1) is bonded is a saturated ring structure, such ascyclohexane, pyran, or dioxane, R^(M1) is preferably a linear alkylgroup having 1 to 5 carbon atoms, a linear alkoxy group having 1 to 4carbon atoms, or a linear alkenyl group having 2 to 5 carbon atoms.

Further the compound represented by the general formula (I) ispreferably a compound selected from a compound group represented bygeneral formula (I-1).

(In the formula, R¹¹ and R¹² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms,or an alkenyl group having 2 to 5 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(I-1) can be properly used in combination according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc. For example,according to an embodiment of the present invention, the number of thetype of compound used is 1. According to another embodiment of thepresent invention, the number of the types is 2. According to stillanother embodiment of the present invention, the number of the types is3. According to a further embodiment of the present invention, thenumber of the types is 4. According to a further embodiment of thepresent invention, the number of the types is 5 or more.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of a compound represented bythe general formula (I-1) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 70% by mass. According toanother embodiment of the present invention, the content is 15% to 70%by mass. According to still another embodiment of the present invention,the content is 18% to 70% by mass. According to a further embodiment ofthe present invention, the content is 25% to 70% by mass. According to afurther embodiment of the present invention, the content is 29% to 70%by mass. According to a further embodiment of the present invention, thecontent is 31% to 70% by mass. According to a further embodiment of thepresent invention, the content is 35% to 70% by mass. According to afurther embodiment of the present invention, the content is 43% to 70%by mass. According to a further embodiment of the present invention, thecontent is 47% to 70% by mass. According to a further embodiment of thepresent invention, the content is 50% to 70% by mass. According to afurther embodiment of the present invention, the content is 53% to 70%by mass. According to a further embodiment of the present invention, thecontent is 56% to 70% by mass.

Further, for example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 3% to 70% bymass. According to another embodiment of the present invention, thecontent is 3% to 60% by mass. According to still another embodiment ofthe present invention, the content is 3% to 50% by mass. According to afurther embodiment of the present invention, the content is 3% to 45% bymass. According to a further embodiment of the present invention, thecontent is 3% to 40% by mass. According to a further embodiment of thepresent invention, the content is 3% to 35% by mass. According to afurther embodiment of the present invention, the content is 3% to 30% bymass. According to a further embodiment of the present invention, thecontent is 3% to 26% by mass.

When the viscosity of the liquid crystal composition of the presentinvention is kept low, and the liquid crystal composition having fastresponse is required, both the lower limit value and the upper limitvalue are preferably high. Further, when Tni of the liquid crystalcomposition of the present invention is kept high, and the liquidcrystal composition having good temperature stability is required, boththe lower limit value and the upper limit value are preferably medium.In addition, when it is desired to increase dielectric anisotropy forkeeping the drive voltage low, both the lower limit value and the upperlimit value are preferably low.

The compound represented by the general formula (I-1) is preferably acompound selected from a compound group represented by general formula(I-1-1).

(In the formula, R¹² represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 5 carbon atoms.)

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (I-1-1) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 60% by mass. According toanother embodiment of the present invention, the content is 4% to 60% bymass. According to still another embodiment of the present invention,the content is 7% to 60% by mass. According to a further embodiment ofthe present invention, the content is 11% to 60% by mass. According to afurther embodiment of the present invention, the content is 13% to 60%by mass. According to a further embodiment of the present invention, thecontent is 15% to 60% by mass. According to a further embodiment of thepresent invention, the content is 17% to 60% by mass. According to afurther embodiment of the present invention, the content is 20% to 60%by mass. According to a further embodiment of the present invention, thecontent is 25% to 60% by mass. According to a further embodiment of thepresent invention, the content is 30% to 60% by mass. According to afurther embodiment of the present invention, the content is 32% to 60%by mass. According to a further embodiment of the present invention, thecontent is 35% to 60% by mass.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 60% by mass. According toanother embodiment of the present invention, the content is 2% to 50% bymass. According to still another embodiment of the present invention,the content of is 2% to 40% by mass. According to a further embodimentof the present invention, the content is 2% to 35% by mass. According toa further embodiment of the present invention, the content is 2% to 30%by mass. According to a further embodiment of the present invention, thecontent is 2% to 25% by mass. According to a further embodiment of thepresent invention, the content is 2% to 20% by mass. According to afurther embodiment of the present invention, the content is 2% to 15% bymass.

Further, the compound represented by the general formula (I-1-1) ispreferably a compound selected from a compound group represented byformula (1.1) to formula (1.3), a compound represented by the formula(1.2) or the formula (1.3) is preferred, and a compound represented bythe formula (1.3) is particularly preferred.

When the compound represented by the formula (1.2) or the formula (1.3)is used singly, the compound represented by the formula (1.2) at aslightly high content is preferred because it has the effect ofimproving the response speed, and the compound represented by theformula (1.3) at a content within a range described below is preferredbecause a liquid crystal composition having fast response and highelectric and optical reliability can be produced.

The content of the compound represented by the formula (1.3) relative tothe total mass of the liquid crystal composition of the presentinvention is preferably 5% by mass or more and 35% by mass or less, morepreferably 5% by mass or more and 30% by mass or less, still morepreferably 5% by mass or more and 25% by mass or less, particularlypreferably 5% by mass or more and 20% by mass or less, and mostpreferably 5% by mass or more and 17% by mass or less.

Examples of the content within the most preferred range include 5% bymass or more and 15% by mass or less, 5% by mass or more and 12% by massor less, 5% by mass or more and 10% by mass or less, 5% by mass or moreand 8% by mass or less, 5% by mass or more and 7% by mass or less, 7% bymass or more and 17% by mass or less, 8% by mass or more and 17% by massor less, 10% by mass or more and 17% by mass or less, 12% by mass ormore and 17% by mass or less, 14% by mass or more and 17% by mass orless, and 15% by mass or more and 17% by mass or less.

Further, the compound represented by the general formula (I-1) ispreferably a compound selected from a compound group represented bygeneral formula (I-1-2).

(In the formula, R¹² represents an alkyl group having 1 to 5 carbonatoms, an alkoxy group having 1 to 5 carbon atoms, or an alkenyl grouphaving 2 to 5 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(I-1-2) can be properly used in combination according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc. For example,according to an embodiment of the present invention, the number of thetype of compound used is 1. According to another embodiment of thepresent invention, the number of the types is 2. According to stillanother embodiment of the present invention, the number of the types is3.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (I-1-2) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 7% to 60% by mass. According toanother embodiment of the present invention, the content is 15% to 60%by mass. According to still another embodiment of the present invention,the content is 18% to 60% by mass. According to a further embodiment ofthe present invention, the content is 21% to 60% by mass. According to afurther embodiment of the present invention, the content is 24% to 60%by mass. According to a further embodiment of the present invention, thecontent is 27% to 60% by mass. According to a further embodiment of thepresent invention, the content is 30% to 60% by mass. According to afurther embodiment of the present invention, the content is 34% to 60%by mass. According to a further embodiment of the present invention, thecontent is 37% to 60% by mass. According to a further embodiment of thepresent invention, the content is 41% to 60% by mass. According to afurther embodiment of the present invention, the content is 47% to 60%by mass. According to a further embodiment of the present invention, thecontent is 50% to 60% by mass.

Further, for example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 7% to 60% bymass. According to another embodiment of the present invention, thecontent is 7% to 55% by mass. According to still another embodiment ofthe present invention, the content is 7% to 45% by mass. According to afurther embodiment of the present invention, the content is 7% to 40% bymass. According to a further embodiment of the present invention, thecontent is 7% to 35% by mass. According to a further embodiment of thepresent invention, the content is 7% to 30% by mass. According to afurther embodiment of the present invention, the content is 7% to 25% bymass. According to a further embodiment of the present invention, thecontent is 7% to 20% by mass.

Further, the compound represented by the general formula (I-1-2) ispreferably a compound selected from a compound group represented byformula (2.1) to formula (2.4), and compounds represented by the formula(2.2) to the formula (2.4) are preferred. In particular, a compoundrepresented by the formula (2.2) is particularly preferred for improvingthe response speed of the liquid crystal composition of the presentinvention. In addition, when high Tni rather than the response speed isrequired, a compound represented by the formula (2.3) or the formula(2.4) is preferably used. Each of the compounds represented by theformula (2.3) and the formula (2.4) at a content of 30% or more isundesired for improving solubility at a low temperature.

In the liquid crystal composition of the present invention, the contentof the compound represented by the formula (2.2) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 5% by mass or more and 55% by mass or less. More preferredexamples of the content include 10% by mass or more and 40% by mass orless, 14% by mass or more and 40% by mass or less, 17% by mass or moreand 40% by mass or less, 19% by mass or more and 40% by mass or less,22% by mass or more and 40% by mass or less, 25% by mass or more and 40%by mass or less, 27% by mass or more and 40% by mass or less, 30% bymass or more and 40% by mass or less, 33% by mass or more and 40% bymass or less, and 36% by mass or more and 40% by mass or less.

Among these ranges, 25% by mass or more and 40% by mass or less isparticularly preferred. Examples of the content within the particularlypreferred range include 25% by mass or more and 35% by mass or less, 25%by mass or more and 30% by mass or less, 30% by mass or more and 40% bymass or less, and 35% by mass or more and 40% by mass or less.

In the liquid crystal composition of the present invention, the contentof the compound represented by the formula (2.3) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 5% by mass or more and 55% by mass or less, more preferably5% by mass or more and 45% by mass or less, even more preferably 5% bymass or more and 35% by mass or less, even more preferably 5% by mass ormore and 25% by mass or less, still more preferably 5% by mass or moreand 20% by mass or less, particularly preferably 8% by mass or more and18% by mass or less, and most preferably 11% by mass or more and 15% bymass or less. Examples of the content within the most preferred rangeinclude 11% by mass or more and 13% by mass or less and 14% by mass ormore and 15% by mass or less.

In the liquid crystal composition of the present invention, the contentof the compound represented by the formula (2.4) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 1% by mass or more and 55% by mass or less, more preferably3% by mass or more and 45% by mass or less, even more preferably 3% bymass or more and 35% by mass or less, still more preferably 3% by massor more and 25% by mass or less, particularly preferably 5% by mass ormore and 15% by mass or less, and most preferably 8% by mass or more and12% by mass or less.

The liquid crystal composition of the present invention can furthercontain a compound represented by formula (2.5) having a structuresimilar to the compound represented by the general formula (I-1-2).

The content of the compound represented by the formula (2.5) ispreferably adjusted according to the desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. The content of the compound relative tothe total mass of the liquid crystal composition of the presentinvention is preferably 11% by mass or more, more preferably 15% by massor more, even more preferably 23% by mass or more, still more preferably26% by mass or more, and particularly preferably 28% by mass or more.

Further, the compound represented by the general formula (I) ispreferably a compound selected from a compound group represented bygeneral formula (I-2).

(In the formula, R¹³ and R¹⁴ each independently represent an alkyl grouphaving 1 to 5 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(I-2) can be properly used in combination according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc. For example,according to an embodiment of the present invention, the number of thetype of compound used is 1. According to another embodiment of thepresent invention, the number of the types is 2. According to stillanother embodiment of the present invention, the number of the types is3.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (I-2) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 60% by mass. According toanother embodiment of the present invention, the content is 4% to 60% bymass. According to still another embodiment of the present invention,the content is 15% to 60% by mass. According to a further embodiment ofthe present invention, the content is 25% to 60% by mass. According to afurther embodiment of the present invention, the content is 30% to 60%by mass. According to a further embodiment of the present invention, thecontent is 35% to 60% by mass. According to a further embodiment of thepresent invention, the content is 38% to 60% by mass. According to afurther embodiment of the present invention, the content is 40% to 60%by mass. According to a further embodiment of the present invention, thecontent is 42% to 60% by mass. According to a further embodiment of thepresent invention, the content is 45% to 60% by mass. According to afurther embodiment of the present invention, the content is 47% to 60%by mass. According to a further embodiment of the present invention, thecontent is 50% to 60% by mass.

Further, for example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 3% to 60% bymass. According to another embodiment of the present invention, thecontent is 3% to 55% by mass. According to still another embodiment ofthe present invention, the content is 3% to 45% by mass. According to afurther embodiment of the present invention, the content is 3% to 40% bymass. According to a further embodiment of the present invention, thecontent is 3% to 30% by mass. According to a further embodiment of thepresent invention, the content is 3% to 20% by mass. According to afurther embodiment of the present invention, the content is 3% to 15% bymass. According to a further embodiment of the present invention, thecontent is 3% to 5% by mass.

The compound represented by the general formula (I-2) is preferably acompound selected from a compound group represented by formula (3.1) toformula (3.4), and a compound represented by the formula (3.1), theformula (3.3), or the formula (3.4) is preferred. In particular, acompound represented by the formula (3.2) is particularly preferred forimproving the response speed of the liquid crystal composition of thepresent invention. In addition, when high Tni rather than the responsespeed is required, a compound represented by the formula (3.3) or theformula (3.4) is preferably used. It is undesired for improvingsolubility at a low temperature that the content of each of thecompounds represented by the formula (3.3) and the formula (3.4) is 20%or more.

The compound represented by the general formula (I-2) is preferably acompound selected from a compound group represented by formula (3.1) toformula (3.4), and a compound represented by the formula (3.1), theformula (3.3) and/or the formula (3.4) is preferred.

In the liquid crystal composition of the present invention, the contentof the compound represented by the formula (3.3) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 2% by mass or more and 40% by mass or less. Examples of amore preferred content include 3% by mass or more and 40% by mass orless, 4% by mass or more and 40% by mass or less, 10% by mass or moreand 40% by mass or less, 12% by mass or more and 40% by mass or less,14% by mass or more and 40% by mass or less, 16% by mass or more and 40%by mass or less, 20% by mass or more and 40% by mass or less, 23% bymass or more and 40% by mass or less, 26% by mass or more and 40% bymass or less, 30% by mass or more and 40% by mass or less, 34% by massor more and 40% by mass or less, 37% by mass or more and 40% by mass orless, 3% by mass or more and 4% by mass or less, 3% by mass or more and10% by mass or less, 3% by mass or more and 12% by mass or less, 3% bymass or more and 14% by mass or less, 3% by mass or more and 16% by massor less, 3% by mass or more and 20% by mass or less, 3% by mass or moreand 23% by mass or less, 3% by mass or more and 26% by mass or less, 3%by mass or more and 30% by mass or less, 3% by mass or more and 34% bymass or less, 3% by mass or more and 37% by mass or less, and 2% by massor more and 6% by mass or less.

Among these contents, 2% by mass or more and 6% by mass or less isparticularly preferred.

Further, the compound represented by the general formula (I) ispreferably a compound selected from a compound group represented bygeneral formula (I-3).

(In the formula, R¹³ represents an alkyl group having 1 to 5 carbonatoms, and R¹⁵ represents an alkoxy group having 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(I-3) can be properly used in combination according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc. For example,according to an embodiment of the present invention, the number of thetype of compound used is 1. According to another embodiment of thepresent invention, the number of the types is 2. According to stillanother embodiment of the present invention, the number of the types is3.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (1-3) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% by mass. According to anotherembodiment of the present invention, the content is 4% to 60% by mass.According to still another embodiment of the present invention, thecontent is 15% to 60% by mass. According to a further embodiment of thepresent invention, the content is 25% to 60% by mass. According to afurther embodiment of the present invention, the content is 30% to 60%by mass. According to a further embodiment of the present invention, thecontent is 35% to 60% by mass. According to a further embodiment of thepresent invention, the content is 38% to 60% by mass. According to afurther embodiment of the present invention, the content is 40% to 60%by mass. According to a further embodiment of the present invention, thecontent is 42% to 60% by mass. According to a further embodiment of thepresent invention, the content is 45% to 60% by mass. According to afurther embodiment of the present invention, the content is 47% to 60%by mass. According to a further embodiment of the present invention, thecontent is 50% to 60% by mass.

Further, for example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 3% to 60% bymass. According to another embodiment of the present invention, thecontent is 3% to 55% by mass. According to still another embodiment ofthe present invention, the content is 3% to 45% by mass. According to afurther embodiment of the present invention, the content is 3% to 40% bymass. According to a further embodiment of the present invention, thecontent is 3% to 30% by mass. According to a further embodiment of thepresent invention, the content is 3% to 20% by mass. According to afurther embodiment of the present invention, the content is 3% to 15% bymass. According to a further embodiment of the present invention, thecontent is 3% to 5% by mass.

When solubility at a low temperature is regarded as important, aslightly high content has a high effect, while when the response speedis regarded as important, a slightly low content has a high effect. Whendropping marks and image sticking are improved, the content range ispreferably determined to a medium range.

The compound represented by the general formula (I-3) is preferably acompound selected from a compound group represented by formula (4.1) toformula (4.3), and a compound represented by the formula (4.3) ispreferred.

The content of the compound represented by the formula (4.3) relative tothe total mass of the liquid crystal composition of the presentinvention is preferably 2% by mass or more and 30% by mass or less, morepreferably 4% by mass or more and 30% by mass or less, more preferably6% by mass or more and 30% by mass or less, more preferably 8% by massor more and 30% by mass or less, more preferably 10% by mass or more and30% by mass or less, more preferably 12% by mass or more and 30% by massor less, more preferably 14% by mass or more and 30% by mass or less,more preferably 16% by mass or more and 30% by mass or less, morepreferably 18% by mass or more and 25% by mass or less, more preferably20% by mass or more and 24% by mass or less, and particularly preferably22% by mass or more and 23% by mass or less.

Further, the compound represented by the general formula (I) ispreferably a compound selected from a compound group represented bygeneral formula (I-4).

(In the formula, R¹¹ and R¹² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 4 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(I-4) can be used in combination according to desired performance suchas solubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to another embodiment of the present invention, the number ofthe types is 2.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (I-4) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 50% by mass. According toanother embodiment of the present invention, the content is 5% to 50% bymass. According to still another embodiment of the present invention,the content is 6% to 50% by mass. According to a further embodiment ofthe present invention, the content is 8% to 50% by mass. According to afurther embodiment of the present invention, the content is 10% to 50%by mass. According to a further embodiment of the present invention, thecontent is 12% to 50% by mass. According to a further embodiment of thepresent invention, the content is 15% to 50% by mass. According to afurther embodiment of the present invention, the content is 20% to 50%by mass. According to a further embodiment of the present invention, thecontent is 25% to 50% by mass. According to a further embodiment of thepresent invention, the content is 30% to 50% by mass. According to afurther embodiment of the present invention, the content is 35% to 50%by mass. According to a further embodiment of the present invention, thecontent is 40% to 50% by mass.

Further, for example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 3% to 50% bymass. According to another embodiment of the present invention, thecontent is 3% to 40% by mass. According to still another embodiment ofthe present invention, the content is 3% to 35% by mass. According to afurther embodiment of the present invention, the content is 3% to 30% bymass. According to a further embodiment of the present invention, thecontent is 3% to 20% by mass. According to a further embodiment of thepresent invention, the content is 3% to 15% by mass. According to afurther embodiment of the present invention, the content is 3% to 10% bymass. According to a further embodiment of the present invention, thecontent is 3% to 5% by mass.

When high birefringence is required, a slightly high content has a higheffect, while when high Tni is regarded as important, a slightly lowcontent has a high effect. When dropping marks and image sticking areimproved, the content range is preferably determined to a medium range.

Further, the compound represented by the general formula (1-4) ispreferably a compound selected from a compound group represented byformula (5.1) to formula (5.4), and compounds represented by the formula(5.2) to formula (5.4) are preferred.

The content of the compound represented by the formula (5.3) relative tothe total mass of the liquid crystal composition of the presentinvention is preferably 1% by mass or more and 30% by mass or less, morepreferably 2% by mass or more and 20% by mass or less, still morepreferably 2% by mass or more and 10% by mass or less, and particularlypreferably 3% by mass or more and 7% by mass or less. Examples of thecontent within the particularly preferred range include 3% by mass ormore and 5% by mass or less and 5% by mass or more and 7% by mass orless.

The content of the compound represented by the formula (5.4) relative tothe total mass of the liquid crystal composition of the presentinvention is preferably 2% by mass or more and 30% by mass or less.Examples of a more preferred content include 4% by mass or more and 30%by mass or less, 6% by mass or more and 30% by mass or less, 8% by massor more and 30% by mass or less, 10% by mass or more and 30% by mass orless, 12% by mass or more and 30% by mass or less, 14% by mass or moreand 30% by mass or less, 16% by mass or more and 30% by mass or less,18% by mass or more and 30% by mass or less, 20% by mass or more and 30%by mass or less, 22% by mass or more and 30% by mass or less, 23% bymass or more and 30% by mass or less, 24% by mass or more and 30% bymass or less, 25% by mass or more and 30% by mass or less, 4% by mass ormore and 6% by mass or less, 4% by mass or more and 8% by mass or less,4% by mass or more and 10% by mass or less, 4% by mass or more and 12%by mass or less, 4% by mass or more and 14% by mass or less, 4% by massor more and 16% by mass or less, 4% by mass or more and 18% by mass orless, 4% by mass or more and 20% by mass or less, 4% by mass or more and22% by mass or less, 4% by mass or more and 23% by mass or less, 4% bymass or more and 24% by mass or less, and 4% by mass or more and 25% bymass or less.

Further, the compound represented by the general formula (I) ispreferably a compound selected from a compound group represented bygeneral formula (I-5).

(In the formula, R¹¹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms, and R¹² represents an alkyl group having 1to 5 carbon atoms, an alkenyl group having 4 to 5 carbon atoms, or analkoxy group having 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(I-5) can be properly used in combination according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc. For example,according to an embodiment of the present invention, the number of thetype of compound used is 1. According to another embodiment of thepresent invention, the number of the types is 2.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (I-5) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 1% to 50% by mass. According toanother embodiment of the present invention, the content is 5% to 50% bymass. According to still another embodiment of the present invention,the content is 8% to 50% by mass. According to a further embodiment ofthe present invention, the content is 11% to 50% by mass. According to afurther embodiment of the present invention, the content is 13% to 50%by mass. According to a further embodiment of the present invention, thecontent is 15% to 50% by mass. According to a further embodiment of thepresent invention, the content is 17% to 50% by mass. According to afurther embodiment of the present invention, the content is 20% to 50%by mass. According to a further embodiment of the present invention, thecontent is 25% to 50% by mass. According to a further embodiment of thepresent invention, the content is 30% to 50% by mass. According to afurther embodiment of the present invention, the content is 35% to 50%by mass. According to a further embodiment of the present invention, thecontent is 40% to 50% by mass.

Further, for example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 1% to 50% bymass. According to another embodiment of the present invention, thecontent is 1% to 40% by mass. According to still another embodiment ofthe present invention, the content is 1% to 35% by mass. According to afurther embodiment of the present invention, the content is 1% to 30% bymass. According to a further embodiment of the present invention, thecontent is 1% to 20% by mass. According to a further embodiment of thepresent invention, the content is 1% to 15% by mass. According to afurther embodiment of the present invention, the content is 1% to 10% bymass. According to a further embodiment of the present invention, thecontent is 1% to 5% by mass.

When solubility at a low temperature is regarded as important, aslightly high content has a high effect, while when the response speedis regarded as important, a slightly low content has a high effect. Whendropping marks and image sticking are improved, the content range ispreferably determined to a medium range.

Further, the compound represented by the general formula (1-5) ispreferably a compound selected from a compound group represented byformula (6.1) to formula (6.6), and compounds represented by the formula(6.3), the formula (6.4), and the formula (6.6) are preferred.

The content of the compound represented by the formula (6.3) relative tothe total mass of the liquid crystal composition of the presentinvention is preferably 2% by mass or more and 30% by mass or less, morepreferably 4% by mass or more and 25% by mass or less, still morepreferably 6% by mass or more and 20% by mass or less, and particularlypreferably 8% by mass or more and 14% by mass or less. Examples of thecontent within the particularly preferred range include 8% by mass ormore and 11% by mass or less and 11% by mass or more and 14% by mass orless.

For example, the content of the compound represented by the formula(6.6) relative to the total mass of the liquid crystal composition ofthe present invention is preferably 2% by mass or more and 30% by massor less, more preferably 4% by mass or more and 30% by mass or less,more preferably 5% by mass or more and 30% by mass or less, morepreferably 6% by mass or more and 30% by mass or less, more preferably9% by mass or more and 30% by mass or less, more preferably 12% by massor more and 30% by mass or less, more preferably 14% by mass or more and30% by mass or less, more preferably 16% by mass or more and 30% by massor less, more preferably 18% by mass or more and 25% by mass or less,more preferably 20% by mass or more and 24% by mass or less, andparticularly preferably 22% by mass or more and 23% by mass or less.

The liquid crystal composition of the present invention can furthercontain compounds represented by formula (6.7) and formula (6.8) as thecompound represented by the general formula (I-5).

The content of the compound represented by the formula (6.7) ispreferably adjusted according to desired performance such as solubilityat a low temperature, transition temperature, electric reliability,birefringence, etc., and the content of the compound relative to thetotal mass of the liquid crystal composition of the present invention ispreferably 2% by mass or more, more preferably 3% by mass or more, stillmore preferably 5% by mass or more, and particularly preferably 7% bymass or more.

Further, the compound represented by the general formula (I) ispreferably a compound selected from a compound group represented bygeneral formula (I-6).

(In the formula, R¹¹ and R¹² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 4 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms, X¹¹ and X¹² eachindependently represent a fluorine atom or a hydrogen atom, and one ofX¹¹ and X¹² is a fluorine atom.)

The content of the compound represented by the general formula (I-6)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 2% by mass or more and 30% by mass orless, more preferably 4% by mass or more and 30% by mass or less, morepreferably 5% by mass or more and 30% by mass or less, more preferably6% by mass or more and 30% by mass or less, more preferably 9% by massor more and 30% by mass or less, more preferably 12% by mass or more and30% by mass or less, more preferably 14% by mass or more and 30% by massor less, more preferably 16% by mass or more and 30% by mass or less,more preferably 18% by mass or more and 25% by mass or less, morepreferably 20% by mass or more and 24% by mass or less, and particularlypreferably 22% by mass or more and 23% by mass or less.

Further, the compound represented by the general formula (I-6) ispreferably a compound represented by formula (7.1).

Further, the compound represented by the general formula (I) ispreferably a compound selected from a compound group represented bygeneral formula (I-7).

(In the formula, R¹¹ and R¹² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms, and X¹² eachindependently represent a fluorine atom or a hydrogen atom.)

The content of the compound represented by the general formula (I-7)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 1% by mass or more and 30% by mass orless, more preferably 2% by mass or more and 30% by mass or less, morepreferably 3% by mass or more and 30% by mass or less, more preferably4% by mass or more and 30% by mass or less, more preferably 6% by massor more and 30% by mass or less, more preferably 8% by mass or more and30% by mass or less, more preferably 10% by mass or more and 30% by massor less, more preferably 12% by mass or more and 30% by mass or less,more preferably 15% by mass or more and 25% by mass or less, morepreferably 18% by mass or more and 24% by mass or less, and particularlypreferably 21% by mass or more and 22% by mass or less.

Further, the compound represented by the general formula (I-7) ispreferably a compound represented by formula (8.1).

Further, the compound represented by the general formula (I) ispreferably a compound selected from a compound group represented bygeneral formula (I-8).

(In the formula, R¹⁶ and R¹⁷ each independently represent an alkenylgroup having 2 to 5 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(I-8) are preferably used alone or in combination of two or threeaccording to desired performance such as solubility at a lowtemperature, transition temperature, electric reliability,birefringence, etc. According to desired performance such as solubilityat a low temperature, transition temperature, electric reliability,birefringence, process adaptability, dropping marks, image sticking,dielectric anisotropy, etc., the content of the compound represented bythe general formula (I-8) relative to the total mass of the liquidcrystal composition of the present invention is preferably 5% by mass ormore and 65% by mass or less, more preferably 10% by mass or more and65% by mass or less, more preferably 15% by mass or more and 65% by massor less, more preferably 20% by mass or more and 65% by mass or less,more preferably 25% by mass or more and 65% by mass or less, morepreferably 30% by mass or more and 65% by mass or less, more preferably35% by mass or more and 65% by mass or less, more preferably 40% by massor more and 65% by mass or less, more preferably 45% by mass or more and60% by mass or less, more preferably 50% by mass or more and 58% by massor less, and particularly preferably 55% by mass or more and 56% by massor less.

Further, the compound represented by the general formula (1-8) ispreferably a compound selected from a compound group represented byformula (9.1) to formula (9.10), and compounds represented by theformula (9.2), the formula (9.4), and the formula (9.7) are preferred.

Further, the compound represented by the general formula (L) ispreferably, for example, a compound selected from compounds representedby general formula (II).

(R²¹ and R²² each independently represent an alkenyl group having 2 to 5carbon atoms, an alkyl group having 1 to 5 carbon atoms, or an alkoxygroup having 1 to 4 carbon atoms, A² represents a 1,4-cyclohexylenegroup or a 1,4-phenylene group, and Q² represents a single bond, —COO—,—CH₂—CH₂—, or —CF₂O—.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(II) can be used in combination according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to still another embodiment of the present invention, thenumber of the types is 2. According to a further embodiment of thepresent invention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4 ormore.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (II) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 50% by mass. According toanother embodiment of the present invention, the content is 5% to 50% bymass. According to still another embodiment of the present invention,the content is 7% to 50% by mass. According to a further embodiment ofthe present invention, the content is 10% to 50% by mass. According to afurther embodiment of the present invention, the content is 14% to 50%by mass. According to a further embodiment of the present invention, thecontent is 16% to 50% by mass. According to a further embodiment of thepresent invention, the content is 20% to 50% by mass. According to afurther embodiment of the present invention, the content is 23% to 50%by mass. According to a further embodiment of the present invention, thecontent is 26% to 50% by mass. According to a further embodiment of thepresent invention, the content is 30% to 50% by mass. According to afurther embodiment of the present invention, the content is 35% to 50%by mass. According to a further embodiment of the present invention, thecontent is 40% to 50% by mass.

Further, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 50% by mass. According toanother embodiment of the present invention, the content is 3% to 40% bymass. According to still another embodiment of the present invention,the content is 3% to 35% by mass. According to a further embodiment ofthe present invention, the content is 3% to 30% by mass. According to afurther embodiment of the present invention, the content is 3% to 20% bymass. According to a further embodiment of the present invention, thecontent is 3% to 15% by mass. According to a further embodiment of thepresent invention, the content is 3% to 10% by mass. According to afurther embodiment of the present invention, the content is 3% to 5% bymass.

Further, the compound represented by the general formula (II) ispreferably, for example, a compound selected from a compound grouprepresented by general formula (II-1).

(R²¹ and R²² each independently represent an alkenyl group having 2 to 5carbon atoms, an alkyl group having 1 to 5 carbon atoms, or an alkoxygroup having 1 to 4 carbon atoms.)

The content of the compound represented by the general formula (II-1) ispreferably adjusted according to desired performance such as solubilityat a low temperature, transition temperature, electric reliability,birefringence, etc., and is preferably 4% by mass or more and 24% bymass or less, more preferably 8% by mass or more and 18% by mass orless, and still more preferably 12% by mass or more and 14% by mass orless.

Further, preferred examples of the compound represented by the generalformula (II-1) include compounds represented by formula (10.1) andformula (10.2).

Further, the compound represented by the general formula (II) ispreferably, for example, a compound selected from a compound grouprepresented by general formula (II-2).

(R²³ represents an alkenyl group having 2 to 5 carbon atoms, and R²⁴represents an alkyl group having 1 to 5 carbon atoms or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(II-2) can be used in combination according to desired performance suchas solubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to still another embodiment of the present invention, thenumber of the types is 2 or more.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (II-2) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 50% by mass. According toanother embodiment of the present invention, the content is 5% to 50% bymass. According to still another embodiment of the present invention,the content is 7% to 50% by mass. According to a further embodiment ofthe present invention, the content is 10% to 50% by mass. According to afurther embodiment of the present invention, the content is 14% to 50%by mass. According to a further embodiment of the present invention, thecontent is 16% to 50% by mass. According to a further embodiment of thepresent invention, the content is 20% to 50% by mass. According to afurther embodiment of the present invention, the content is 23% to 50%by mass. According to a further embodiment of the present invention, thecontent is 26% to 50% by mass. According to a further embodiment of thepresent invention, the content is 30% to 50% by mass. According to afurther embodiment of the present invention, the content is 35% to 50%by mass. According to a further embodiment of the present invention, thecontent is 40% to 50% by mass.

Further, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 50% by mass. According toanother embodiment of the present invention, the content is 3% to 40% bymass. According to still another embodiment of the present invention,the content is 3% to 35% by mass. According to a further embodiment ofthe present invention, the content is 3% to 30% by mass. According to afurther embodiment of the present invention, the content is 3% to 20% bymass. According to a further embodiment of the present invention, thecontent is 3% to 15% by mass. According to a further embodiment of thepresent invention, the content is 3% to 10% by mass. According to afurther embodiment of the present invention, the content is 3% to 5% bymass.

Further, preferred examples of the compound represented by the generalformula (II-2) include compounds represented by formula (11.1) toformula (11.3).

According to desired performance such as solubility at a lowtemperature, transition temperature, electric reliability,birefringence, etc., the liquid crystal composition of the presentinvention may contain a compound represented by the formula (11.1), acompound represented by the formula (11.2), both a compound representedby the formula (11.1) and a compound represented by the formula (11.2),or all compounds represented by the formula (11.1) to the formula(11.3). The content of the compound represented by the formula (11.1) orthe formula (11.2) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 3% by mass or moreand 40% by mass or less, more preferably 5% by mass or more and 35% bymass or less, still more preferably 5% by mass or more and 30% by massor less, particularly preferably 5% by mass or more and 25% by mass orless, and most preferably 5% by mass or more and 20% by mass or less.Examples of the content within the most preferred range include 8% bymass or more and 20% by mass or less, 12% by mass or more and 20% bymass or less, 15% by mass or more and 20% by mass or less, 5% by mass ormore and 18% by mass or less, 5% by mass or more and 15% by mass orless, 5% by mass or more and 12% by mass or less, 5% by mass or more and10% by mass or less, and 5% by mass or more and 8% by mass or less.

The content of the compound represented by the formula (11.1) relativeto the total mass of the liquid crystal composition of the presentinvention is preferably 3% by mass or more and 40% by mass or less, morepreferably 5% by mass or more and 35% by mass or less, still morepreferably 5% by mass or more and 30% by mass or less, yet morepreferably 5% by mass or more and 25% by mass or less, and particularlypreferably 5% by mass or more and 20% by mass or less. Examples of thecontent within the particularly preferred range include 5% by mass ormore and 17% by mass or less, 5% by mass or more and 15% by mass orless, 5% by mass or more and 12% by mass or less, 5% by mass or more and10% by mass or less, 5% by mass or more and 8% by mass or less, 6% bymass or more and 20% by mass or less, 8% by mass or more and 20% by massor less, 10% by mass or more and 20% by mass or less, 12% by mass ormore and 20% by mass or less, 15% by mass or more and 20% by mass orless, and 17% by mass or more and 20% by mass or less.

The content of the compound represented by the formula (11.2) relativeto the total mass of the liquid crystal composition of the presentinvention is preferably 3% by mass or more and 40% by mass or less, morepreferably 3% by mass or more and 35% by mass or less, still morepreferably 3% by mass or more and 30% by mass or less, yet morepreferably 3% by mass or more and 25% by mass or less, particularlypreferably 3% by mass or more and 20% by mass or less, and mostpreferably 5% by mass or more and 12% by mass or less.

Examples of the content within the most preferred range include 5% bymass or more and 10% by mass or less, 5% by mass or more and 8% by massor less, 5% by mass or more and 6% by mass or less, 6% by mass or moreand 12% by mass or less, 8% by mass or more and 12% by mass or less, and10% by mass or more and 12% by mass or less.

When both the compound represented by the formula (11.1) and thecompound represented by the formula (11.2) are contained, the total massof both compounds relative to the total mass of the liquid crystalcomposition of the present invention is preferably 10% by mass or moreand 45% by mass or less, more preferably 13% by mass or more and 35% bymass or less, and still more preferably 16% by mass or more and 25% bymass or less.

Examples of the content within the still more preferred range include16% by mass or more and 22% by mass or less, 16% by mass or more and 20%by mass or less, 16% by mass or more and 18% by mass or less, 18% bymass or more and 25% by mass or less, 20% by mass or more and 25% bymass or less, and 22% by mass or more and 25% by mass or less.

Further, the compound represented by the general formula (II) ispreferably, for example, a compound selected from a compound grouprepresented by general formula (II-3).

(R²⁵ represents an alkyl group having 1 to 5 carbon atoms, and R²⁴represents an alkyl group having 1 to 5 carbon atoms or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(II-3) are preferably used alone or in combination of two or threeaccording to desired performance such as solubility at a lowtemperature, transition temperature, electric reliability,birefringence, etc.

It is necessary to properly adjust the content of the compoundrepresented by the general formula (II-3) according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, process adaptability,dropping marks, image sticking, dielectric anisotropy, etc. The contentof the compound relative to the total mass of the liquid crystalcomposition of the present invention is, for example, 2% to 45% by mass.Examples of the more preferred content include 5% to 45% by mass, 8% to45% by mass, 11% to 45% by mass, 14% to 45% by mass, 17% to 45% by mass,20% to 45% by mass, 23% to 45% by mass, 26% to 45% by mass, 29% to 45%by mass, 2% to 45% by mass, 2% to 40% by mass, 2% to 35% by mass, 2% to30% by mass, 2% to 25% by mass, 2% to 20% by mass, 2% to 15% by mass,and 2% to 10% by mass.

Further, preferred examples of the compound represented by the generalformula (II-3) include compounds represented by formula (12.1) toformula (12.3).

According to desired performance such as solubility at a lowtemperature, transition temperature, electric reliability,birefringence, etc., the liquid crystal composition of the presentinvention may contain a compound represented by the formula (12.1), acompound represented by the formula (12.2), or both a compoundrepresented by the formula (12.1) and a compound represented by theformula (12.2). The content of the compound represented by the formula(12.1) or the formula (12.2) relative to the total mass of the liquidcrystal composition of the present invention is preferably 3% by mass ormore and 40% by mass or less, more preferably 5% by mass or more and 40%by mass or less, even more preferably 7% by mass or more and 40% by massor less, even more preferably 9% by mass or more and 40% by mass orless, still more preferably 11% by mass or more and 40% by mass or less,still more preferably 12% by mass or more and 40% by mass or less, stillmore preferably 13% by mass or more and 40% by mass or less, still morepreferably 18% by mass or more and 30% by mass or less, and particularlypreferably 21% by mass or more and 25% by mass or less. The content ofthe compound represented by the formula (12.2) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 3% by mass or more and 40% by mass or less, more preferably5% by mass or more and 40% by mass or less, even more preferably 8% bymass or more and 40% by mass or less, even more preferably 10% by massor more and 40% by mass or less, still more preferably 12% by mass ormore and 40% by mass or less, still more preferably 15% by mass or moreand 40% by mass or less, still more preferably 17% by mass or more and30% by mass or less, and particularly preferably 19% by mass or more and25% by mass or less. When both the compound represented by the formula(12.1) and the compound represented by the formula (12.2) are contained,the total mass of both compounds relative to the total mass of theliquid crystal composition of the present invention is preferably 15% bymass or more and 45% by mass or less, more preferably 19% by mass ormore and 45% by mass or less, still more preferably 24% by mass or moreand 40% by mass or less, and particularly preferably 30% by mass or moreand 35% by mass or less.

The content of the compound represented by the formula (12.3) relativeto the total mass of the liquid crystal composition of the presentinvention is preferably 0.05% by mass or more and 2% by mass or less,more preferably 0.1% by mass or more and 1% by mass or less, and stillmore preferably 0.2% by mass or more and 0.5% by mass or less. Thecompound represented by the formula (12.3) may be an optically activecompound.

Further, the compound represented by the general formula (II-3) ispreferably, for example, a compound selected from a compound grouprepresented by general formula (II-3-1).

(R²⁵ represents an alkyl group having 1 to 5 carbon atoms, and R²⁶represents an alkoxy group having 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but one to three of compounds represented by the generalformula (II-3-1) are preferably contained according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc.

It is preferred to properly adjust the content of the compoundrepresented by the general formula (II-3-1) according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc., and the contentof the compound is preferably 1% by mass or more and 24% by mass orless, more preferably 4% by mass or more and 18% by mass or less, andstill more preferably 8% by mass or more and 14% by mass or less.

Further, preferred examples of the compound represented by the generalformula (II-3-1) include compounds represented by formula (13.1) toformula (13.4), and a compound represented by formula (13.3) isparticularly preferred.

Further, the compound represented by the general formula (II) ispreferably, for example, a compound selected from a compound grouprepresented by general formula (II-4).

(R²¹ and R²² each independently represent an alkenyl group having 2 to 5carbon atoms, an alkyl group having 1 to 5 carbon atoms, or an alkoxygroup having 1 to 4 carbon atoms.)

These compounds may be contained alone or in combination of two or moreand are preferably properly combined according to desired performance.The types of compounds which can be combined are not particularlylimited, but one or two, particularly preferably one to three, of aplurality of compounds represented by the general formula (II-4) arepreferably contained according to desired performance such as solubilityat a low temperature, transition temperature, electric reliability,birefringence, etc.

The content of the compound represented by the general formula (II-4)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 1% by mass or more and 15% by mass orless, more preferably 2% by mass or more and 15% by mass or less, evenmore preferably 3% by mass or more and 15% by mass or less, still morepreferably 4% by mass or more and 12% by mass or less, and particularlypreferably 5% by mass or more and 7% by mass or less.

Further, preferred examples of the compound represented by the generalformula (II-4) include compounds represented by formula (14.1) toformula (14.5), and a compound represented by formula (14.2) or formula(14.5) is particularly preferred.

Further, the compound represented by the general formula (L) ispreferably a compound selected from a compound group represented bygeneral formula (III).

(R³¹ and R³² each independently represent an alkenyl group having 2 to 5carbon atoms, an alkyl group having 1 to 5 carbon atoms, or an alkoxygroup having 1 to 4 carbon atoms.)

In view of desired solubility, birefringence, etc., the content of thecompound represented by the general formula (III) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 3% by mass or more and 25% by mass or less, more preferably6% by mass or more and 20% by mass or less, and still more preferably 8%by mass or more and 15% by mass or less.

Further, the compound represented by the general formula (III) ispreferably, for example, a compound represented by formula (15.1) orformula (15.2), and a compound represented by formula (15.1) isparticularly preferred.

Further, the compound represented by the general formula (III) ispreferably a compound selected from a compound group represented bygeneral formula (III-1).

(R³³ represents an alkenyl group having 2 to 5 carbon atoms. R³²represents an alkyl group having 1 to 5 carbon atoms or an alkoxy grouphaving 1 to 4 carbon atoms.)

The content of the compound represented by the general formula (III-1)is preferably adjusted according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc., and the content of the compound ispreferably 4% by mass or more and 23% by mass or less, more preferably6% by mass or more and 18% by mass or less, and still more preferably10% by mass or more and 13% by mass or less.

Further, the compound represented by the general formula (III-1) ispreferably, for example, a compound represented by formula (16.1) orformula (16.2).

Further, the compound represented by the general formula (III) ispreferably a compound selected from a compound group represented bygeneral formula (III-2).

(R³¹ represents an alkyl group having 1 to 5 carbon atoms, and R³⁴represents an alkoxy group having 1 to 4 carbon atoms.)

The content of the compound represented by the general formula (III-2)is preferably adjusted according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc., and the content of the compound ispreferably 4% by mass or more and 23% by mass or less, more preferably6% by mass or more and 18% by mass or less, and still more preferably10% by mass or more and 13% by mass or less.

Further, the compound represented by the general formula (III-2) ispreferably, for example, a compound selected from a compound grouprepresented by formula (17.1) to formula (17.3), and a compoundrepresented by formula (17.3) is particularly preferred.

Further, the compound represented by the general formula (L) ispreferably a compound selected from a group represented by generalformula (IV).

(In the formula, R⁴¹ and R⁴² each independently represent an alkyl grouphaving 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbonatoms, and X⁴¹ and X⁴² each independently represent a hydrogen atom or afluorine atom.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(IV) can be used in combination according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to still another embodiment of the present invention, thenumber of the types is 2. According to a further embodiment of thepresent invention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4.According to a further embodiment of the present invention, the numberof the types is 5. According to a further embodiment of the presentinvention, the number of the types is 6 or more.

Further, the compound represented by the general formula (IV) ispreferably, for example, a compound selected from a compound grouprepresented by general formula (IV-1).

(In the formula, R⁴³ and R⁴⁴ each independently represent an alkyl grouphaving 1 to 5 carbon atoms.)

It is necessary to properly adjust the content of the compoundrepresented by the general formula (IV-1) according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, process adaptability,dropping marks, image sticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 1% to 40% by mass. According toanother embodiment of the present invention, the content is 2% to 40% bymass. According to still another embodiment of the present invention,the content is 4% to 40% by mass. According to a further embodiment ofthe present invention, the content is 6% to 40% by mass. According to afurther embodiment of the present invention, the content is 8% to 40% bymass. According to a further embodiment of the present invention, thecontent is 10% to 40% by mass. According to a further embodiment of thepresent invention, the content is 12% to 40% by mass. According to afurther embodiment of the present invention, the content is 15% to 40%by mass. According to a further embodiment of the present invention, thecontent is 18% to 40% by mass. According to a further embodiment of thepresent invention, the content is 21% to 40% by mass.

Further, for example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 1% to 40% bymass. According to another embodiment of the present invention, thecontent is 1% to 30% by mass. According to still another embodiment ofthe present invention, the content is 1% to 25% by mass. According to afurther embodiment of the present invention, the content is 1% to 20% bymass. According to a further embodiment of the present invention, thecontent is 1% to 15% by mass. According to a further embodiment of thepresent invention, the content is 1% to 10% by mass. According to afurther embodiment of the present invention, the content is 1% to 5% bymass. According to a further embodiment of the present invention, thecontent is 1% to 4% by mass.

Further, preferred examples of the compound represented by the generalformula (IV-1) include compounds represented by formula (18.1) toformula (18.9).

The types of compounds which can be combined are not particularlylimited, but one to three, more preferably one to four, of thesecompounds are preferably contained. Also, since it is effective forsolubility that the compound selected has a wide molecular weightdistribution, for example, one compound represented by the formula(18.1) or the formula (18.2), one compound represented by the formula(18.4) or the formula (18.5), one compound represented by the formula(18.6) or the formula (18.7), and one compound represented by theformula (18.8) or the formula (18.9) are preferably selected andappropriately combined. In particular, the compounds represented by theformula (18.1), the formula (18.3), the formula (18.4), the formula(18.6), and the formula (18.9) are preferably contained.

Further, the compound represented by the general formula (IV) ispreferably, for example, a compound selected from a compound grouprepresented by general formula (IV-2).

(In the formula, R⁴⁵ and R⁴⁶ each independently represent an alkyl grouphaving 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbonatoms, at least one of R⁴⁵ and R⁴⁶ represents an alkenyl group having 2to 5 carbon atoms, and X⁴¹ and X⁴² each independently represent ahydrogen atom or a fluorine atom.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(IV-2) can be used in combination according to desired performance suchas solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

It is necessary to properly adjust the content of the compoundrepresented by the general formula (IV-2) according to desiredperformance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, process adaptability,dropping marks, image sticking, dielectric anisotropy, etc. For example,the content of the compound relative to the total mass of the liquidcrystal composition of the present invention is preferably 0.5% to 40%by mass. Examples of a more preferred content include 1% to 40% by mass,2% to 40% by mass, 3% to 40% by mass, 5% to 40% by mass, 7% to 40% bymass, 9% to 40% by mass, 12% to 40% by mass, 15% to 40% by mass, 20% to40% by mass, 1% to 40% by mass, 1% to 30% by mass, 1% to 25% by mass, 1%to 20% by mass, 1% to 15% by mass, 1% to 10% by mass, 1% to 5% by mass,and 1% to 4% by mass.

Further, preferred examples of the compound represented by the generalformula (IV-2) include compounds represented by formula (19.1) toformula (19.8), and a compound represented by formula (19.2) isparticularly preferred.

Since it is effective for solubility that the compound selected as acomponent of the liquid crystal composition has a wide molecular weightdistribution, for example, one compound represented by the formula(19.1) or the formula (19.2), one compound represented by the formula(19.3) or the formula (19.4), one compound represented by the formula(19.5) or the formula (19.6), and one compound represented by theformula (19.7) or the formula (19.8) are preferably selected andappropriately combined.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by thegeneral formula (19.2) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 0.5% by mass or moreand 15% by mass or less, more preferably 1% by mass or more and 10% bymass or less, still more preferably 1% by mass or more and 7% by mass orless, particularly preferably 1% by mass or more and 5% by mass or less,and most preferably 1% by mass or more and 3% by mass or less.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by thegeneral formula (19.4) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 3% by mass or moreand 25% by mass or less, more preferably 5% by mass or more and 20% bymass or less, still more preferably 5% by mass or more and 15% by massor less, and particularly preferably 7% by mass or more and 10% by massor less.

Further, the compound represented by the general formula (L) ispreferably a compound selected from a group represented by generalformula (V).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms, A⁵¹ and A⁵² eachindependently represent a 1,4-cyclhexylene group or a 1,4-phenylenegroup, Q² represents a single bond or —COO—, and X⁵¹ and X⁵² eachindependently represent a fluorine atom or a hydrogen atom.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(V) can be used in combination according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to still another embodiment of the present invention, thenumber of the types is 2. According to a further embodiment of thepresent invention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 40% by mass. According toanother embodiment of the present invention, the content is 4% to 40% bymass. According to still another embodiment of the present invention,the content is 7% to 40% by mass. According to a further embodiment ofthe present invention, the content is 10% to 40% by mass. According to afurther embodiment of the present invention, the content is 12% to 40%by mass. According to a further embodiment of the present invention, thecontent is 15% to 40% by mass. According to a further embodiment of thepresent invention, the content is 17% to 40% by mass. According to afurther embodiment of the present invention, the content is 18% to 40%by mass. According to a further embodiment of the present invention, thecontent is 20% to 40% by mass. According to a further embodiment of thepresent invention, the content is 22% to 40% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass of the liquidcrystal composition of the present invention is 2% to 40% by mass.According to another embodiment of the present invention, the content ofthe compound is 2% to 30% by mass. According to still another embodimentof the present invention, the content of the compound is 2% to 25% bymass. According to a further embodiment of the present invention, thecontent of the compound is 2% to 20% by mass. According to a furtherembodiment of the present invention, the content of the compound is 2%to 15% by mass. According to a further embodiment of the presentinvention, the content of the compound is 2% to 10% by mass. Accordingto a further embodiment of the present invention, the content of thecompound is 2% to 5% by mass. According to a further embodiment of thepresent invention, the content of the compound is 2% to 4% by mass.

Further, the compound represented by the general formula (V) ispreferably a compound represented by general formula (V-1).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms, and X⁵¹ and X⁵² eachindependently represent a fluorine atom or a hydrogen atom.)

Further, the compound represented by the general formula (V-1) ispreferably a compound represented by general formula (V-1-1).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms.)

The content of the compound represented by the general formula (V-1-1)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 1% by mass or more and 15% by mass orless, more preferably 2% by mass or more and 15% by mass or less, stillmore preferably 3% by mass or more and 10% by mass or less, andparticularly preferably 4% by mass or more and 8% by mass or less.

Further, preferred examples of the compound represented by the generalformula (V-1-1) include compounds represented by formula (20.1) toformula (20.4), and a compound represented by formula (20.2) isparticularly preferred.

Further, the compound represented by the general formula (V-1) ispreferably a compound represented by general formula (V-1-2).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms.)

The content of the compound represented by the general formula (V-1-2)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 1% by mass or more and 15% by mass orless, more preferably 2% by mass or more and 15% by mass or less, stillmore preferably 3% by mass or more and 10% by mass or less, andparticularly preferably 4% by mass or more and 8% by mass or less.

Further, preferred examples of the compound represented by the generalformula (V-1-2) include compounds represented by formula (21.1) toformula (21.3), and a compound represented by formula (21.1) isparticularly preferred.

Further, the compound represented by the general formula (V-1) ispreferably a compound represented by general formula (V-1-3).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms.)

The content of the compound represented by the general formula (V-1-3)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 1% by mass or more and 15% by mass orless, more preferably 2% by mass or more and 15% by mass or less, stillmore preferably 3% by mass or more and 10% by mass or less, andparticularly preferably 4% by mass or more and 8% by mass or less.

Further, examples of the compound represented by the general formula(V-1-3) include compounds represented by formula (22.1) to formula(22.3), and a compound represented by formula (22.1) is particularlypreferred.

Further, the compound represented by the general formula (V) ispreferably a compound represented by general formula (V-2).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms, and X⁵¹ and X⁵² eachindependently represent a fluorine atom or a hydrogen atom.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(V-2) can be used in combination according to desired performance suchas solubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to another embodiment of the present invention, the number ofthe types is 2 or more.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 40% by mass. According toanother embodiment of the present invention, the content of the compoundis 4% to 40% by mass. According to still another embodiment of thepresent invention, the content of the compound is 7% to 40% by mass.According to a further embodiment of the present invention, the contentof the compound is 10% to 40% by mass. According to a further embodimentof the present invention, the content of the compound is 12% to 40% bymass. According to a further embodiment of the present invention, thecontent of the compound is 15% to 40% by mass. According to a furtherembodiment of the present invention, the content of the compound is 17%to 40% by mass. According to a further embodiment of the presentinvention, the content of the compound is 18% to 40% by mass. Accordingto a further embodiment of the present invention, the content of thecompound is 20% to 40% by mass. According to a further embodiment of thepresent invention, the content of the compound is 22% to 40% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass of the liquidcrystal composition of the present invention is 2% to 40% by mass.According to another embodiment of the present invention, the content ofthe compound is 2% to 30% by mass. According to still another embodimentof the present invention, the content of the compound is 2% to 25% bymass. According to a further embodiment of the present invention, thecontent of the compound is 2% to 20% by mass. According to a furtherembodiment of the present invention, the content of the compound is 2%to 15% by mass. According to a further embodiment of the presentinvention, the content of the compound is 2% to 10% by mass. Accordingto a further embodiment of the present invention, the content of thecompound is 2% to 5% by mass. According to a further embodiment of thepresent invention, the content of the compound is 2% to 4% by mass.

When an embodiment in which the liquid crystal composition of thepresent invention has high Tni is desired, the content of the compoundrepresented by the formula (V-2) is preferably slightly increased, whilewhen an embodiment in which the liquid crystal composition of thepresent invention has low viscosity is desired, the content ispreferably slightly decreased.

Further, the compound represented by the general formula (V-2) ispreferably a compound represented by general formula (V-2-1).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms.)

Further, preferred examples of the compound represented by the generalformula (V-2-1) include compounds represented by formula (23.1) toformula (23.4), and a compound represented by formula (23.1) or formula(23.2) is particularly preferred.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by theformula (23.1) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 1% by mass or moreand 25% by mass or less, more preferably 1% by mass or more and 15% bymass or less, still more preferably 1% by mass or more and 10% by massor less, and particularly preferably 3% by mass or more and 8% by massor less.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by theformula (23.2) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 1% by mass or moreand 25% by mass or less, more preferably 1% by mass or more and 15% bymass or less, still more preferably 1% by mass or more and 10% by massor less, and particularly preferably 3% by mass or more and 8% by massor less.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the total content of the compound represented by theformula (23.1) and the compound represented by the formula (23.2)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 1% by mass or more and 25% by mass orless, more preferably 3% by mass or more and 20% by mass or less, stillmore preferably 6% by mass or more and 15% by mass or less, andparticularly preferably 8% by mass or more and 12% by mass or less.

Further, the compound represented by the general formula (V-2) ispreferably a compound represented by general formula (V-2-2).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms.)

Further, preferred examples of the compound represented by the generalformula (V-2-2) include compounds represented by formula (24.1) toformula (24.4), and a compound represented by formula (24.1) or formula(24.2) is particularly preferred.

Further, the compound represented by the general formula (V) ispreferably a compound represented by general formula (V-3).

(In the formula, R⁵¹ and R⁵² each independently represent an alkyl grouphaving 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms,or an alkoxy group having 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(V-3) can be used in combination according to desired performance suchas solubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to still another embodiment of the present invention, thenumber of the types is 2. According to a further embodiment of thepresent invention, the number of the types is 3 or more.

The content of the compound represented by the general formula (V-3)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 2% by mass or more and 16% by mass orless, more preferably 4% by mass or more and 16% by mass or less, stillmore preferably 7% by mass or more and 13% by mass or less, andparticularly preferably 8% by mass or more and 11% by mass or less.

Further, preferred examples of the compound represented by the generalformula (V-3) include compounds represented by formula (25.1) to formula(25.3).

The liquid crystal composition of the present invention can furthercontain at least one compound represented by general formula (VI).

(In the formula, R⁶¹ and R⁶² each independently represent a linear alkylgroup having 1 to 10 carbon atoms, a linear alkoxy group having 1 to 10carbon atoms, or a linear alkenyl group having 2 to 10 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but preferably one to three, more preferably one to four, andparticularly preferably one to five or more, of a plurality of compoundsrepresented by the general formula (VI) are contained according todesired performance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc. In addition, theallowable maximum content is preferably 35% by mass or less, morepreferably 25% by mass or less, and still more preferably 15% by mass orless.

Examples of a compound which can be preferably used as the compoundrepresented by the general formula (VI) are given below.

The liquid crystal composition of the present invention can furthercontain at least one compound represented by general formula (VII).

(In the formula, R⁷¹ and R⁷² each independently represent a linear alkylgroup having 1 to 10 carbon atoms, a linear alkoxy group having 1 to 10carbon atoms, or a linear alkenyl group having 4 to 10 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but preferably one to three, more preferably one to four, andparticularly preferably one to five or more, of a plurality of compoundsrepresented by the general formula (VII) are contained according todesired performance such as solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc. In addition, theallowable maximum content is preferably 35% by mass or less, morepreferably 25% by mass or less, and still more preferably 15% by mass orless.

Examples of a compound which can be preferably used as the compoundrepresented by the general formula (VII) are given below.

The liquid crystal composition of the present invention preferablyfurther contains any one or more of compounds represented by generalformula (M) below.

(In the formula, R^(M1) an alkyl group having 1 to 8 carbon atoms; oneor nonadjacent two or more —CH₂— in the alkyl group may be eachindependently substituted by —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—;

PM represents 0, 1, 2, 3, or 4;

C^(M1) and C^(M2) each independently represent a group selected from thegroup consisting of:

(d) a 1,4-cyclohexylene group (one —CH₂— or nonadjacent two or more—CH₂— present in the group may be substituted by —O— or —S—); and

(e) a 1,4-phenylene group (one —CH═ or nonadjacent two or more —CH═present in the group may be substituted by —N═), and the group (d) andthe group (e) may be each independently substituted by a cyano group, afluorine atom, or a chlorine atom;

K^(M1) and K^(M2) each independently represent a single bond, —CH₂CH₂—,—(CH₂)₄—, —OCH₂—, —CH₂O—, —OCF₂—, —CF₂O—, —COO—, —OCO—, or —C≡C—;

when PM is 2, 3, or 4, and a plurality of K^(M1) are present, K^(M1) maybe the same or different, and when PM is 2, 3, or 4, and a plurality ofC^(M2) are present, C^(M2) may be the same or different;

X^(M1) and X^(M3) each independently represent a hydrogen atom, achlorine atom, or a fluorine atom; and

X^(M2) represents a hydrogen atom, a fluorine atom, a chlorine atom, acyano group, a trifluoromethyl group, a fluoromethoxy group, adifluoromethoxy group, a trifluoromethoxy group, or a2,2,2-trifluoroethyl group. However, compounds represented by thegeneral formula (i) and general formula (ii) are excluded.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(M) can be used in combination according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to another embodiment of the present invention, the number ofthe types is 2. According to still another embodiment of the presentinvention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4.According to a further embodiment of the present invention, the numberof the types is 5. According to a further embodiment of the presentinvention, the number of the types is 6. According to a furtherembodiment of the present invention, the number of the types is 7 ormore.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (M) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 1% to 95% by mass. For example,according to another embodiment of the present invention, the content ofthe compound is 10% to 95% by mass. For example, according to stillanother embodiment of the present invention, the content of the compoundis 20% to 95% by mass. For example, according to a further embodiment ofthe present invention, the content of the compound is 30% to 95% bymass. For example, according to a further embodiment of the presentinvention, the content of the compound is 40% to 95% by mass. Forexample, according to a further embodiment of the present invention, thecontent of the compound is 45% to 95% by mass. For example, according toa further embodiment of the present invention, the content of thecompound is 50% to 95% by mass. For example, according to a furtherembodiment of the present invention, the content of the compound is 55%to 95% by mass. For example, according to a further embodiment of thepresent invention, the content of the compound is 60% to 95% by mass.For example, according to a further embodiment of the present invention,the content of the compound is 65% to 95% by mass. For example,according to a further embodiment of the present invention, the contentof the compound is 70% to 95% by mass. For example, according to afurther embodiment of the present invention, the content of the compoundis 75% to 95% by mass. For example, according to a further embodiment ofthe present invention, the content of the compound is 80% to 95% bymass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass of the liquidcrystal composition of the present invention is 1% to 95% by mass.According to another embodiment of the present invention, the content ofthe compound is 1% to 85% by mass. According to still another embodimentof the present invention, the content of the compound is 1% to 75% bymass. According to a further embodiment of the present invention, thecontent of the compound is 1% to 65% by mass. According to a furtherembodiment of the present invention, the content of the compound is 1%to 55% by mass. According to a further embodiment of the presentinvention, the content of the compound is 1% to 45% by mass. Accordingto a further embodiment of the present invention, the content of thecompound is 1% to 35% by mass. According to a further embodiment of thepresent invention, the content of the compound is 1% to 25% by mass.

When the viscosity of the liquid crystal composition of the presentinvention is kept low, and the liquid crystal composition having fastresponse is required, both the lower limit value and the upper limitvalue are preferably slightly low. Further, when Tni of the liquidcrystal composition of the present invention is kept high, and theliquid crystal composition having good temperature stability isrequired, both the lower limit value and the upper limit value arepreferably slightly low. In addition, when it is desired to increasedielectric anisotropy for keeping the drive voltage low, both the lowerlimit value and the upper limit value are preferably slightly high.

When a ring structure to which R^(M1) is bonded is a phenyl group(aromatic), R^(M1) is preferably a linear alkyl group having 1 to 5carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms, or analkenyl group having 4 to 5 carbon atoms, while when a ring structure towhich R^(M1) is bonded is a saturated ring structure, such ascyclohexane, pyran, or dioxane, R^(M1) is preferably a linear alkylgroup having 1 to 5 carbon atoms, a linear alkoxy group having 1 to 4carbon atoms, or a linear alkenyl group having 2 to 5 carbon atoms.

When the liquid crystal composition is required to have chemicalstability, a compound represented by the general formula (M) preferablydoes not contain a chlorine atom in its molecule. Further, the liquidcrystal composition preferably contains 5% or less, preferably 3% orless, preferably 1% or less, preferably 0.5% or less, of a compoundhaving a chlorine atom and preferably substantially does not contain thecompound. The expression “substantially does not contain” representsthat the liquid crystal composition is contaminated with only anunintentional compound having a chlorine atom such as a compoundproduced as impurities during production of the compound.

The compound represented by the general formula (M) is preferably, forexample, a compound selected from a compound group represented bygeneral formula (VIII).

(In the formula, R⁸ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms, X⁸¹ to X⁸⁵ each independently represent ahydrogen atom or a fluorine atom, and Y⁸ represents a fluorine atom or—OCF₃.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(VIII) can be used in combination according to desired performance suchas solubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to another embodiment of the present invention, the number ofthe types is 2. According to a further embodiment of the presentinvention, the number of the types is 3 or more.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (VIII) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 40% by mass. For example,according to another embodiment of the present invention, the content ofthe compound is 4% to 40% by mass. For example, according to stillanother embodiment of the present invention, the content of the compoundis 5% to 40% by mass. For example, according to a further embodiment ofthe present invention, the content of the compound is 6% to 40% by mass.For example, according to a further embodiment of the present invention,the content of the compound is 7% to 40% by mass. For example, accordingto a further embodiment of the present invention, the content of thecompound is 8% to 40% by mass. For example, according to a furtherembodiment of the present invention, the content of the compound is 9%to 40% by mass. For example, according to a further embodiment of thepresent invention, the content of the compound is 10% to 40% by mass.For example, according to a further embodiment of the present invention,the content of the compound is 11% to 40% by mass. For example,according to a further embodiment of the present invention, the contentof the compound is 12% to 40% by mass. For example, according to afurther embodiment of the present invention, the content of the compoundis 14% to 40% by mass. For example, according to a further embodiment ofthe present invention, the content of the compound is 15% to 40% bymass. For example, according to a further embodiment of the presentinvention, the content of the compound is 21% to 40% by mass. Forexample, according to a further embodiment of the present invention, thecontent of the compound is 23% to 40% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass of the liquidcrystal composition of the present invention is 2% to 40% by mass.According to another embodiment of the present invention, the content ofthe compound is 2% to 30% by mass. According to still another embodimentof the present invention, the content of the compound is 2% to 25% bymass. According to a further embodiment of the present invention, thecontent of the compound is 2% to 21% by mass. According to a furtherembodiment of the present invention, the content of the compound is 2%to 16% by mass. According to a further embodiment of the presentinvention, the content of the compound is 2% to 12% by mass. Accordingto a further embodiment of the present invention, the content of thecompound is 2% to 8% by mass. According to a further embodiment of thepresent invention, the content of the compound is 2% to 5% by mass.

When the viscosity of the liquid crystal composition of the presentinvention is kept low, and the liquid crystal composition having fastresponse is required, both the lower limit value and the upper limitvalue are preferably slightly low. Further, when Tni of the liquidcrystal composition of the present invention is kept high, and theliquid crystal composition having good temperature stability isrequired, both the lower limit value and the upper limit value arepreferably slightly low. In addition, when it is desired to increasedielectric anisotropy for keeping the drive voltage low, both the lowerlimit value and the upper limit value are preferably slightly high.

The compound represented by the general formula (VIII) is preferably acompound represented by general formula (VIII-1).

(In the formula, R⁸ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(VIII-1) can be used in combination according to desired performancesuch as solubility at a low temperature, transition temperature,electric reliability, birefringence, etc. For example, according to anembodiment of the present invention, the number of the type of compoundused is 1. According to another embodiment of the present invention, thenumber of the types is 2 or more.

Further, preferred examples of the compound represented by the generalformula (VIII-1) include compounds represented by formula (26.1) toformula (26.4), a compound represented by formula (26.1) or formula(26.2) is preferred, and a compound represented by formula (26.2) ismore preferred.

In view of solubility at a low temperature, transition temperature,electric reliability, birefringence, etc., the content of the compoundrepresented by the formula (26.1) relative to the total mass of theliquid crystal composition of the present invention is preferably 1% bymass or more and 40% by mass or less, more preferably 1% by mass or moreand 30% by mass or less, even more preferably 1% by mass or more and 20%by mass or less, even more preferably 2% by mass or more and 15% by massor less, still more preferably 2% by mass or more and 10% by mass orless, and particularly preferably 2% by mass or more and 9% by mass orless. Examples of the content within the particularly preferred rangeinclude 2% by mass or more and 7% by mass or less, 2% by mass or moreand 6% by mass or less, 2% by mass or more and 5% by mass or less, 2% bymass or more and 4% by mass or less, 2% by mass or more and 3% by massor less, 3% by mass or more and 9% by mass or less, 4% by mass or moreand 9% by mass or less, 5% by mass or more and 9% by mass or less, and6% by mass or more and 9% by mass or less.

In view of solubility at a low temperature, transition temperature,electric reliability, birefringence, etc., the content of the compoundrepresented by the formula (26.2) relative to the total mass of theliquid crystal composition of the present invention is preferably 2% bymass or more and 40% by mass or less, more preferably 4% by mass or moreand 30% by mass or less, still more preferably 7% by mass or more and20% by mass or less, and particularly preferably 7% by mass or more and15% by mass or less.

Examples of the content within the particularly preferred range include7% by mass or more and 12% by mass or less, 7% by mass or more and 10%by mass or less, 7% by mass or more and 8% by mass or less, 8% by massor more and 15% by mass or less, 10% by mass or more and 15% by mass orless, and 12% by mass or more and 15% by mass or less.

The total content of the compound represented by the formula (26.1) andthe compound represented by the formula (26.2) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 5% to 40% by mass, more preferably 10% to 30% by mass, stillmore preferably 10% to 25% by mass, and particularly preferably 10% to20% by mass.

Further, the compound represented by the general formula (VIII) ispreferably a compound represented by general formula (VIII-2).

(In the formula, R⁸ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(VIII-2) can be used in combination according to desired performancesuch as solubility at a low temperature, transition temperature,electric reliability, birefringence, etc. For example, according to anembodiment of the present invention, the number of the type of compoundused is 1. According to another embodiment of the present invention, thenumber of the types is 2. According to a further embodiment of thepresent invention, the number of the types is 3 or more.

In view of solubility at a low temperature, transition temperature,electric reliability, birefringence, etc., the content of the compoundrepresented by the general formula (VIII-2) is preferably 2.5% by massor more and 25% by mass or less, preferably 8% by mass or more and 25%by mass or less, more preferably 10% by mass or more and 20% by mass orless, and still more preferably 12% by mass or more and 15% by mass orless.

Further, preferred examples of the compound represented by the generalformula (VIII-2) include compounds represented by formula (27.1) toformula (27.4), and a compound represented by formula (27.2) is morepreferred.

Further, the compound represented by the general formula (VIII) ispreferably a compound represented by general formula (VIII-3).

(In the formula, R⁸ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(VIII-3) can be used in combination according to desired performancesuch as solubility at a low temperature, transition temperature,electric reliability, birefringence, etc. For example, according to anembodiment of the present invention, the number of the type of compoundused is 1. According to another embodiment of the present invention, thenumber of the types is 2 or more.

Further, preferred examples of the compound represented by the generalformula (VIII-3) include compounds represented by formula (26.11) toformula (26.14), a compound represented by formula (26.11) or formula(26.12) is preferred, and a compound represented by formula (26.12) ismore preferred.

The compound represented by the general formula (M) is preferably, forexample, a compound selected from a compound group represented bygeneral formula (IX). However, compounds represented by the generalformula (i) described above are excluded.

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms, X⁹¹ and X⁹² each independently represent ahydrogen atom or a fluorine atom, Y⁹ represents a fluorine atom, achlorine atom, or —OCF₃, and U⁹ represents a single bond, —COO—, or—CF₂O—.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(IX) can be used in combination according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to another embodiment of the present invention, the number ofthe types is 2. According to still another embodiment of the presentinvention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4.According to a further embodiment of the present invention, the numberof the types is 5. According to a further embodiment of the presentinvention, the number of the types is 6 or more.

In the liquid crystal composition of the present invention, it isnecessary to properly adjust the content of the compound represented bythe general formula (Ix) according to desired performance such assolubility at a low temperature, transition temperature, electricreliability, birefringence, process adaptability, dropping marks, imagesticking, dielectric anisotropy, etc.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 70% by mass. For example,according to another embodiment of the present invention, the content ofthe compound is 5% to 70% by mass. For example, according to stillanother embodiment of the present invention, the content of the compoundis 8% to 70% by mass. For example, according to a further embodiment ofthe present invention, the content of the compound is 10% to 70% bymass. For example, according to a further embodiment of the presentinvention, the content of the compound is 12% to 70% by mass. Forexample, according to a further embodiment of the present invention, thecontent of the compound is 15% to 70% by mass. For example, according toa further embodiment of the present invention, the content of thecompound is 17% to 70% by mass. For example, according to a furtherembodiment of the present invention, the content of the compound is 20%to 70% by mass. For example, according to a further embodiment of thepresent invention, the content of the compound is 24% to 70% by mass.For example, according to a further embodiment of the present invention,the content of the compound is 28% to 70% by mass. For example,according to a further embodiment of the present invention, the contentof the compound is 30% to 70% by mass. For example, according to afurther embodiment of the present invention, the content of the compoundis 34% to 70% by mass. For example, according to a further embodiment ofthe present invention, the content of the compound is 39% to 70% bymass. For example, according to a further embodiment of the presentinvention, the content of the compound is 40% to 70% by mass. Forexample, according to a further embodiment of the present invention, thecontent of the compound is 42% to 70% by mass. For example, according toa further embodiment of the present invention, the content of thecompound is 45% to 70% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass of the liquidcrystal composition of the present invention is 3% to 70% by mass.According to another embodiment of the present invention, the content ofthe compound is 3% to 60% by mass. According to still another embodimentof the present invention, the content of the compound is 3% to 55% bymass. According to a further embodiment of the present invention, thecontent of the compound is 3% to 50% by mass. According to a furtherembodiment of the present invention, the content of the compound is 3%to 45% by mass. According to a further embodiment of the presentinvention, the content of the compound is 3% to 40% by mass. Accordingto a further embodiment of the present invention, the content of thecompound is 3% to 35% by mass. According to a further embodiment of thepresent invention, the content of the compound is 3% to 30% by mass.According to a further embodiment of the present invention, the contentof the compound is 25% by mass. According to a further embodiment of thepresent invention, the content of the compound is 3% to 20% by mass.According to a further embodiment of the present invention, the contentof the compound is 3% to 15% by mass. According to a further embodimentof the present invention, the content of the compound is 3% to 10% bymass.

When the viscosity of the liquid crystal composition of the presentinvention is kept low, and the liquid crystal composition having fastresponse is required, both the lower limit value and the upper limitvalue are preferably slightly low. Further, when Tni of the liquidcrystal composition of the present invention is kept high, and theliquid crystal composition causing little image sticking is required,both the lower limit value and the upper limit value are preferablyslightly low. In addition, when it is desired to increase dielectricanisotropy for keeping the drive voltage low, both the lower limit valueand the upper limit value are preferably slightly high.

The compound represented by the general formula (IX) is preferably acompound represented by general formula (IX-1).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms, X⁹² represents a hydrogen atom or a fluorineatom, and Y⁹ represents a fluorine atom or —OCF₃.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(IX-1) can be used in combination according to desired performance suchas solubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to another embodiment of the present invention, the number ofthe types is 2. According to still another embodiment of the presentinvention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4 ormore.

Further, the compound represented by the general formula (IX-1) ispreferably a compound represented by general formula (IX-1-1).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(IX-1-1) can be used in combination according to desired performancesuch as solubility at a low temperature, transition temperature,electric reliability, birefringence, etc. For example, according to anembodiment of the present invention, the number of the type of compoundused is 1. According to another embodiment of the present invention, thenumber of the types is 2.

In view of solubility at a low temperature, transition temperature,electric reliability, birefringence, etc., the content of the compoundrepresented by the general formula (IX-1-1) relative to the total massof the liquid crystal composition of the present invention has preferredupper limit and lower limit values according to an embodiment.

According to an embodiment, the content of the compound relative to thetotal mass is 1% to 40% by mass. According to another embodiment, thecontent of the compound is 1% to 35% by mass. According to still anotherembodiment, the content of the compound is 1% to 30% by mass. Accordingto a further embodiment, the content of the compound is 1% to 25% bymass. According to a further embodiment, the content of the compound is1% to 10% by mass. According to a further embodiment, the content of thecompound is 1% to 7% by mass. According to a further embodiment, thecontent of the compound is 1% to 5% by mass.

Further, preferred examples of the compound represented by the generalformula (IX-1-1) include compounds represented by formula (28.1) toformula (28.5). The liquid crystal composition preferably contains anyone or two of the compounds represented by formula (28.3) and formula(28.5).

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by theformula (28.3) relative to the total mass of the liquid crystalcomposition is preferably 1% by mass or more and 30% by mass or less,more preferably 2% by mass or more and 20% by mass or less, still morepreferably 2% by mass or more and 15% by mass or less, particularlypreferably 2% by mass or more and 12% by mass or less, and mostpreferably 2% by mass or more and 10% by mass or less.

Examples of the content within the most preferred range include 2% bymass or more and 8% by mass or less, 2% by mass or more and 6% by massor less, 2% by mass or more and 4% by mass or less, 4% by mass or moreand 10% by mass or less, 6% by mass or more and 10% by mass or less, and8% by mass or more and 10% by mass or less.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by theformula (28.5) relative to the total mass of the liquid crystalcomposition is preferably 3% by mass or more and 25% by mass or less,more preferably 5% by mass or more and 20% by mass or less, still morepreferably 5% by mass or more and 15% by mass or less, and particularlypreferably 5% by mass or more and 12% by mass or less.

Examples of the content within the particularly preferred range include5% by mass or more and 10% by mass or less, 5% by mass or more and 8% bymass or less, 5% by mass or more and 7% by mass or less, 7% by mass ormore and 12% by mass or less, 8% by mass or more and 12% by mass orless, and 10% by mass or more and 12% by mass or less.

In the liquid crystal composition of the present invention, the totalcontent of the compound represented by the formula (28.3) and thecompound represented by the formula (28.5) relative to the total mass ofthe liquid crystal composition is preferably 5% by mass or more and 30%by mass or less, more preferably 7% by mass or more and 28% by mass orless, still more preferably 9% by mass or more and 26% by mass or less,particularly preferably 11% by mass or more and 24% by mass or less, andmost preferably 13% by mass or more and 22% by mass or less.

Examples of the content within the most preferred range include 13% bymass or more and 20% by mass or less, 13% by mass or more and 18% bymass or less, 13% by mass or more and 16% by mass or less, 13% by massor more and 14% by mass or less, 14% by mass or more and 22% by mass orless, 16% by mass or more and 22% by mass or less, 18% by mass or moreand 22% by mass or less, 20% by mass or more and 22% by mass or less,and 21% by mass or more and 22% by mass or less.

When the liquid crystal composition contains the compound represented bythe formula (28.3) and the compound represented by the formula (28.5),either the compound represented by the formula (28.3) or the compoundrepresented by the formula (28.5) may have a higher relative content.However, from the viewpoint of increasing Tni of the liquid crystalcomposition, the compound represented by the formula (28.5) preferablyhas a higher content.

Further, the compound represented by the general formula (IX-1) ispreferably a compound represented by general formula (IX-1-2).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(IX-1-2) are preferably used alone or in combination of two or three,more two to four, in view of solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of the compound represented bythe general formula (IX-1-2) relative to the total mass of the liquidcrystal composition of the present invention is preferably 1% by mass ormore and 30% by mass or less, more preferably 5% by mass or more and 30%by mass or less, even more preferably 8% by mass or more and 30% by massor less, still more preferably 10% by mass or more and 25% by mass orless, still more preferably 14% by mass or more and 22% by mass or less,and particularly preferably 16% by mass or more and 20% by mass or less.

Further, preferred examples of the compound represented by the generalformula (IX-1-2) include compounds represented by formula (29.1) toformula (29.4), and a compound represented by formula (29.2) or formula(29.4) is preferred.

The compound represented by the general formula (IX) is preferably acompound represented by general formula (IX-2). However, compoundsrepresented by the general formula (i) are excluded.

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms, X⁹¹ and X⁹² each independently represent ahydrogen atom or a fluorine atom, and Y⁹ represents a fluorine atom, achlorine atom, or —OCF₃.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(IX-2) can be used in combination according to each embodiment in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1;according to another embodiment, the number of the types combined is 2;according to still another embodiment, the number of the types combinedis 3; according to a further embodiment, the number of the typescombined is 4; according to a further embodiment, the number of thetypes combined is 5; and according to a further embodiment, the numberof the types combined is 6 or more.

Further, the compound represented by the general formula (IX-2) ispreferably a compound represented by general formula (IX-2-1).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but a plurality of compounds represented by the general formula(IX-2-1) are preferably used alone or in combination of two or three inview of solubility at a low temperature, transition temperature,electric reliability, birefringence, etc.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of the compound represented by the general formula (IX-2-1) haspreferred upper limit and lower limit values according to eachembodiment.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 1% to 40% by mass. According toanother embodiment, the content of the compound is 2% to 40% by mass.According to still another embodiment, the content of the compound is 4%to 40% by mass. According to a further embodiment, the content of thecompound is 10% to 40% by mass. According to a further embodiment, thecontent of the compound is 14% to 40% by mass. According to a furtherembodiment, the content of the compound is 16% to 40% by mass. Accordingto a further embodiment, the content of the compound is 21% to 40% bymass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 1% to 40% bymass; according to another embodiment, the content of the compound is 1%to 35% by mass; according to still another embodiment, the content ofthe compound is 1% to 30% by mass; according to a further embodiment,the content of the compound is 1% to 25% by mass; according to a furtherembodiment, the content of the compound is 1% to 22% by mass; accordingto a further embodiment, the content of the compound is 1% to 20% bymass; according to a further embodiment, the content of the compound is1% to 10% by mass; according to a further embodiment, the content of thecompound is 1% to 7% by mass; and according to a further embodiment, thecontent of the compound is 1% to 5% by mass.

Further, preferred examples of the compound represented by the generalformula (IX-2-1) include compounds represented by formula (30.1) toformula (30.4), and compounds represented by formula (30.1) and formula(30.2) are preferred.

Further, the compound represented by the general formula (IX-2) ispreferably a compound represented by general formula (IX-2-2).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not limited, but aplurality of compounds represented by the general formula (IX-2-2) arepreferably alone or in combination of two or three, more preferably twoto four, in view of solubility at a low temperature, transitiontemperature, electric reliability, birefringence, etc.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of the compound represented by the general formula (IX-2-2) haspreferred upper limit and lower limit values according to eachembodiment. For example, according to an embodiment of the presentinvention, the content of the compound relative to the total mass of theliquid crystal composition of the present invention is 1% to 40% bymass; according to another embodiment, the content of the compound is 2%to 40% by mass; according to still another embodiment, the content ofthe compound is 4% to 40% by mass; according to a further embodiment,the content of the compound is 10% to 40% by mass; according to afurther embodiment, the content of the compound is 14% to 40% by mass;according to a further embodiment, the content of the compound is 16% to40% by mass; and according to a further embodiment, the content of thecompound is 21% to 40% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 1% to 40% bymass; according to another embodiment, the content of the compound is 1%to 35% by mass; according to still another embodiment, the content ofthe compound is 1% to 30% by mass; according to a further embodiment,the content of the compound is 1% to 25% by mass; according to a furtherembodiment, the content of the compound is 1% to 22% by mass; accordingto a further embodiment, the content of the compound is 1% to 15% bymass; according to a further embodiment, the content of the compound is1% to 12% by mass; according to a further embodiment, the content of thecompound is 1% to 8% by mass; and according to a further embodiment, thecontent of the compound is 1% to 4% by mass.

Further, preferred examples of the compound represented by the generalformula (IX-2-2) include compounds represented by formula (31.1) toformula (31.4), compounds represented by formula (31.2) to formula(31.4) are more preferred, and a compound represented by formula (31.2)is still more preferred.

In the liquid crystal composition of the present invention, the contentof the compound represented by the formula (31.2) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 1% by mass or more and 35% by mass or less, more preferably2% by mass or more and 25% by mass or less, still more preferably 3% bymass or more and 20% by mass or less, particularly preferably 3% by massor more and 15% by mass or less, and most preferably 3% by mass or moreand 11% by mass or less.

Examples of the content within the most preferred range include 3% bymass or more and 8% by mass or less, 3% by mass or more and 6% by massor less, 3% by mass or more and 4% by mass or less, 4% by mass or moreand 11% by mass or less, 6% by mass or more and 11% by mass or less, and8% by mass or more and 11% by mass or less.

In the liquid crystal composition of the present invention, the contentof the compound represented by the formula (31.4) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 1% by mass or more and 35% by mass or less, more preferably1% by mass or more and 25% by mass or less, even more preferably 1% bymass or more and 15% by mass or less, even more preferably 2% by mass ormore and 10% by mass or less, even more preferably 3% by mass or moreand 8% by mass or less, still more preferably 3% by mass or more and 6%by mass or less, and particularly preferably 3% by mass or more and 5%by mass or less.

Further, the compound represented by the general formula (IX-2) ispreferably a compound represented by general formula (IX-2-3).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not limited, but aplurality of compounds represented by the general formula (IX-2-3) arepreferably used alone or in combination of two in view of solubility ata low temperature, transition temperature, electric reliability,birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (IX-2-3) relative to the total mass of the liquidcrystal composition of the present invention is preferably 1% by mass ormore and 30% by mass or less, more preferably 3% by mass or more and 20%by mass or less, even more preferably 6% by mass or more and 15% by massor less, and still more preferably 8% by mass or more and 10% by mass orless.

Further, preferred examples of the compound represented by the generalformula (IX-2-3) include compounds represented by formula (32.1) toformula (32.4), and a compound represented by formula (32.2) and/or acompound represented by formula (32.4) is more preferred.

Further, the compound represented by the general formula (IX-2) ispreferably a compound represented by general formula (IX-2-4).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (IX-2-4) relative to the total mass of the liquidcrystal composition of the present invention is preferably 1% by mass ormore and 30% by mass or less, more preferably 3% by mass or more and 20%by mass or less, still more preferably 6% by mass or more and 15% bymass or less, and particularly preferably 8% by mass or more and 10% bymass or less.

Further, preferred examples of the compound represented by the generalformula (IX-2-4) include compounds represented by formula (33.1) toformula (33.5), and a compound represented by formula (33.1) and/or acompound represented by formula (33.3) is more preferred.

Further, the compound represented by the general formula (IX-2) ispreferably a compound represented by general formula (IX-2-5).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not limited, but aplurality of compounds represented by the general formula (IX-2-5) canbe properly used in combination according to each embodiment in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of type used is 1; according toanother embodiment, the number the types is 2; according to stillanother embodiment, the number of type used is 3; and according to afurther embodiment, the number of type used is 4 or more.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of the compound represented by the general formula (IX-2-5) hasupper limit and lower limit values according to each embodiment. Forexample, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 4% to 45% by mass; according toanother embodiment, the content of the compound is 8% to 45% by mass;according to still another embodiment, the content of the compound is12% to 45% by mass; according to a further embodiment, the content ofthe compound is 21% to 45% by mass; according to a further embodiment,the content of the compound is 30% to 45% by mass; according to afurther embodiment, the content of the compound is 31% to 45% by mass;and according to a further embodiment, the content of the compound is34% to 45% by mass. Also, for example, according to an embodiment of thepresent invention, the content of the compound relative to the totalmass is 4% to 45% by mass; according to another embodiment, the contentof the compound is 4% to 40% by mass; according to still anotherembodiment, the content of the compound is 4% to 35% by mass; accordingto a further embodiment, the content of the compound is 4% to 32% bymass; according to a further embodiment, the content of the compound is4% to 22% by mass; according to a further embodiment, the content of thecompound is 4% to 13% by mass; according to a further embodiment, thecontent of the compound is 4% to 9% by mass; according to a furtherembodiment, the content of the compound is 4% to 8% by mass; andaccording to a further embodiment, the content of the compound is 4% to5% by mass.

When the viscosity of the liquid crystal composition of the presentinvention is kept low, and the liquid crystal composition having fastresponse is required, both the lower limit value and the upper limitvalue are preferably slightly low. Further, when Tni of the liquidcrystal composition of the present invention is kept high, and theliquid crystal composition causing little image sticking is required,both the lower limit value and the upper limit value are preferablyslightly low. In addition, when it is desired to increase dielectricanisotropy for keeping the drive voltage low, both the lower limit valueand the upper limit value are preferably slightly high.

Further, preferred examples of the compound represented by the generalformula (IX-2-5) include compounds represented by formula (34.1) toformula (34.5), and a compound represented by formula (34.1), formula(34.2), formula (34.3), and/or formula (34.5) is more preferred.

The compound represented by the general formula (IX) is preferably acompound represented by general formula (IX-3).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms, X⁹¹ and X⁹² each independently represent ahydrogen atom or a fluorine atom, and Y⁹ represents a fluorine atom, achlorine atom, or —OCF₃.)

Further, the compound represented by the general formula (IX-3) ispreferably a compound represented by general formula (IX-3-1).

(In the formula, R⁹ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not limited, but aplurality of compounds represented by the general formula (IX-3-1) arepreferably used alone or in combination of two in view of solubility ata low temperature, transition temperature, electric reliability,birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (IX-3-1) relative to the total mass of the liquidcrystal composition of the present invention is preferably 3% by mass ormore and 30% by mass or less, more preferably 7% by mass or more and 30%by mass or less, still more preferably 13% by mass or more and 20% bymass or less, and particularly preferably 15% by mass or more and 18% bymass or less.

Further, preferred examples of the compound represented by the generalformula (IX-3-1) include compounds represented by formula (35.1) toformula (35.4), and a compound represented by formula (35.1) and/orformula (35.2) is preferred.

The compound represented by the general formula (M) is preferably acompound represented by general formula (X). However, compoundsrepresented by the general formula (i) and compounds represented by thegeneral formula (ii) described above are excluded.

(In the formula, X¹⁰¹ to X¹⁰⁴ each independently represent a fluorineatom or a hydrogen atom, Y¹⁰ represents a fluorine atom, a chlorineatom, or —OCF₃, Q¹⁰ represents a single bond or —CF₂O—, R^(n) representsan alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to5 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, and A¹⁰¹and A¹⁰² each independently represent a 1,4-cyclohexylene group, a1,4-phenylene group, or

wherein a hydrogen atom on a 1,4-phenylene group may be substituted by afluorine atom.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X) can beproperly used in combination according to each embodiment in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According t another embodiment of the present invention, the number ofthe types is 2. According to still another embodiment, the number of thetypes is 3. According to a further embodiment, the number of the typesis 4. According to a further embodiment, the number of the types is 5 ormore.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of a compound represented by the general formula (X) has anupper limit value and a lower limit value according to each embodiment.For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 45% by mass; according toanother embodiment, the content of the compound is 3% to 45% by mass;according to still another embodiment, the content of the compound is 6%to 45% by mass; according to a further embodiment, the content of thecompound is 8% to 45% by mass; according to a further embodiment, thecontent of the compound is 9% to 45% by mass; according to a furtherembodiment, the content of the compound is 11% to 45% by mass; accordingto a further embodiment, the content of the compound is 12% to 45% bymass; according to a further embodiment, the content of the compound is18% to 45% by mass; according to a further embodiment, the content ofthe compound is 19% to 45% by mass; according to a further embodiment,the content of the compound is 23% to 45% by mass; and according to afurther embodiment, the content of the compound is 25% to 45% by mass.Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 2% to 45% bymass; according to another embodiment, the content of the compound is 2%to 35% by mass; according to still another embodiment, the content ofthe compound is 2% to 30% by mass; according to a further embodiment,the content of the compound is 2% to 25% by mass; according to a furtherembodiment, the content of the compound is 2% to 20% by mass; accordingto a further embodiment, the content of the compound is 2% to 13% bymass; according to a further embodiment, the content of the compound is2% to 9% by mass; according to a further embodiment, the content of thecompound is 2% to 6% by mass; and according to a further embodiment, thecontent of the compound is 2% to 3% by mass.

When the viscosity of the liquid crystal composition of the presentinvention is kept low, and the liquid crystal composition having fastresponse is required, both the lower limit value and the upper limitvalue are preferably slightly low. Further, when the liquid crystalcomposition causing little image sticking is required, both the lowerlimit value and the upper limit value are preferably slightly low. Inaddition, when it is desired to increase dielectric anisotropy forkeeping the drive voltage low, both the lower limit value and the upperlimit value are preferably slightly high.

The compound represented by the general formula (X) is preferably acompound represented by general formula (X-3).

(In the formula, X¹⁰² and X¹⁰³ each independently represent a fluorineatom or a hydrogen atom, and R¹⁰ represents an alkyl group having 1 to 5carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxygroup having 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-3) arepreferably used alone or in combination of two or more in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

Further, the compound represented by the general formula (X-3) and usedin the liquid crystal composition of the present invention is preferablya compound represented by general formula (X-3-1).

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-3-1) arepreferably used alone or in combination of two or more in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

The content of a compound represented by the general formula (X-3-1)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 1% by mass or more, more preferably 2%by mass or more, and still more preferably 3% by mass or more. Inaddition, in view of solubility at a low temperature, transitiontemperature, electric reliability, etc., the maximum ratio is preferablylimited to 10% by mass or less, more preferably 8% by mass or less,still more preferably 6% by mass or less, and particularly preferably 4%by mass or less.

Preferred examples of the compound represented by the general formula(X-3-1) and used in the liquid crystal composition of the presentinvention include compounds represented by formula (41.1) to formula(41.4), and particularly a compound represented by formula (41.2) ispreferably contained.

In the liquid crystal composition of the present invention, the contentof the compound represented by the formula (41.2) relative to the totalmass of the liquid crystal composition of the present invention ispreferably 0.5% by mass or more and 15% by mass or less, more preferably1% by mass or more and 10% by mass or less, still more preferably 1% bymass or more and 7% by mass or less, particularly preferably 1% by massor more and 5% by mass or less, and most preferably 1% by mass or moreand 3% by mass or less.

The compound represented by the general formula (X) is preferably acompound represented by general formula (X-4).

(In the formula, X¹⁰² represents a fluorine atom or a hydrogen atom, andR¹⁰ represents an alkyl group having 1 to 5 carbon atoms, an alkenylgroup having 2 to 5 carbon atoms, or an alkoxy group having 1 to 4carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-4) arepreferably used alone or in combination of two or more and morepreferably used alone or in combination of two or three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

Further, the compound represented by the general formula (X-4) and usedin the liquid crystal composition of the present invention is preferablya compound represented by general formula (X-4-1).

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-4-1) arepreferably used alone or in combination of two or more and morepreferably used alone or in combination of two or three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (X-4-1) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 2% by mass or moreand 20% by mass or less, more preferably 5% by mass or more and 17% bymass or less, still more preferably 10% by mass or more and 15% by massor less, and particularly preferably 10% by mass or more and 13% by massor less.

Further, preferred examples of the compound represented by the generalformula (X-4-1) and used in the liquid crystal composition of thepresent invention include compounds represented by formula (42.1) toformula (42.4), and particularly a compound represented by formula(42.3) is preferably contained.

Further, the compound represented by the general formula (X) and used inthe liquid crystal composition of the present invention is preferably acompound represented by general formula (X-4-2).

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-4-2) arepreferably used alone or in combination of two or more and morepreferably used alone or in combination of two or three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented bygeneral formula (X-4-2) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 2% by mass or moreand 20% by mass or less, more preferably 5% by mass or more and 17% bymass or less, still more preferably 10% by mass or more and 15% by massor less, and particularly preferably 10% by mass or more and 13% by massor less.

Further, preferred examples of the compound represented by the generalformula (X-4-2) and used in the liquid crystal composition of thepresent invention include compounds represented by formula (42.11) toformula (42.14), and particularly a compound represented by formula(42.13) or formula (42.14) is preferably contained.

Further, the compound represented by the general formula (X) and used inthe liquid crystal composition of the present invention is preferably acompound represented by general formula (X-4-3).

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-4-3) arepreferably used alone or in combination of two or more and morepreferably used alone or in combination of two or three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented bygeneral formula (X-4-3) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 2% by mass or moreand 20% by mass or less, more preferably 5% by mass or more and 17% bymass or less, still more preferably 10% by mass or more and 15% by massor less, and particularly preferably 10% by mass or more and 13% by massor less.

Further, preferred examples of the compound represented by the generalformula (X-4-3) and used in the liquid crystal composition of thepresent invention include compounds represented by formula (42.21) toformula (42.24), and particularly a compound represented by formula(42.22) is more preferred.

Further, the compound represented by the general formula (X) ispreferably a compound represented by general formula (X-5).

(In the formula, X¹⁰² represents a fluorine atom or a hydrogen atom, andR¹⁰ represents an alkyl group having 1 to 5 carbon atoms, an alkenylgroup having 2 to 5 carbon atoms, or an alkoxy group having 1 to 4carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-5) arepreferably used alone or in combination of two or more and morepreferably used alone or in combination of two or three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

Further, the compound represented by the general formula (X-5) and usedin the liquid crystal composition of the present invention is preferablya compound represented by general formula (X-5-1).

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X-5-1) arepreferably used alone or in combination of two or more and morepreferably used alone or in combination of two or three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

Further, preferred examples of the compound represented by the generalformula (X-5-1) and used in the liquid crystal composition of thepresent invention include compounds represented by formula (43.1) toformula (43.4), and a compound represented by formula (43.2) isparticularly preferred.

Further, the liquid crystal composition of the present invention mayfurther contain a compound represented by general formula (X′-7) similarto the compound represented by the general formula (X).

(In the formula, R¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (X′-7) arepreferably used alone or in combination of two or more in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of the compound represented by the general formula (X′-7) hasupper limit and lower limit values according to each embodiment.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 4% to 30% by mass; according toanother embodiment, the content of the compound is 5% to 30% by mass;according to still another embodiment, the content of the compound is 6%to 30% by mass; according to a further embodiment, the content of thecompound is 8% to 30% by mass; according to a further embodiment, thecontent of the compound is 9% to 30% by mass; according to a furtherembodiment, the content of the compound is 11% to 30% by mass; accordingto a further embodiment, the content of the compound is 14% to 30% bymass; and according to a further embodiment, the content of the compoundis 18% to 30% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 4% to 30% bymass; according to another embodiment, the content of the compound is 4%to 20% by mass; according to still another embodiment, the content ofthe compound is 4% to 13% by mass; according to a further embodiment,the content of the compound is 4% to 10% by mass; and according to afurther embodiment, the content of the compound is 4% to 7% by mass.

Further, preferred examples of the compound represented by the generalformula (X′-7) and used in the liquid crystal composition of the presentinvention include compounds represented by formula (44.11) to formula(44.14), and particularly a compound represented by formula (44.13) ismore preferred.

Further, the compound represented by the general formula (X) ispreferably a compound selected from a group represented by generalformula (XI).

(In the formula, X¹¹¹ to X¹¹⁷ each independently represent a fluorineatom or a hydrogen atom, at least one of X¹¹¹ to X¹¹⁷ represents afluorine atom, R¹¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms, and Y¹¹ represents a fluorine atom or—OCF₃.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (XI) arepreferably used alone or in combination of two to three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of a compound represented by the general formula (XI) has anupper limit value and a lower limit value according to each embodiment.For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 30% by mass; according toanother embodiment, the content of the compound is 4% to 30% by mass;according to still another embodiment, the content of the compound is 5%to 30% by mass; according to a further embodiment, the content of thecompound is 7% to 30% by mass; according to a further embodiment, thecontent of the compound is 9% to 30% by mass; according to a furtherembodiment, the content of the compound is 10% to 30% by mass; accordingto a further embodiment, the content of the compound is 12% to 30% bymass; according to a further embodiment, the content of the compound is13% to 30% by mass; according to a further embodiment, the content ofthe compound is 15% to 30% by mass; and according to a furtherembodiment, the content of the compound is 18% to 30% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 2% to 30% bymass; according to another embodiment, the content of the compound is 2%to 25% by mass; according to still another embodiment, the content ofthe compound is 2% to 20% by mass; according to a further embodiment,the content of the compound is 2% to 15% by mass; according to a furtherembodiment, the content of the compound is 2% to 10% by mass; andaccording to a further embodiment, the content of the compound is 2% to5% by mass.

When the liquid crystal composition of the present invention is used fora liquid crystal display device having a small cell gap, it is desiredto slightly increase the content of the compound represented by thegeneral formula (XI). When the liquid crystal composition of the presentinvention is used for a liquid crystal display device having a low drivevoltage, it is desired to slightly increase the content of the compoundrepresented by the general formula (XI). When the liquid crystalcomposition of the present invention is used for a liquid crystaldisplay device used in a low-temperature environment, it is desired toslightly decrease the content of the compound represented by the generalformula (XI). When the liquid crystal composition of the presentinvention is used for a liquid crystal display device having fastresponse, it is desired to slightly decrease the content of the compoundrepresented by the general formula (XI).

Further, the compound represented by the general formula (XI) and usedin the liquid crystal composition of the present invention is preferablya compound represented by general formula (XI-1).

(In the formula, R¹¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (XI-1) can beproperly used in combination according to each embodiment in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1;according to another embodiment of the present invention, the number ofthe types is 2; and according to a further embodiment, the number of thetypes is 3 or more.

In view of solubility at a low temperature, transition temperature,electric reliability, birefringence, etc., the content of a compoundrepresented by the general formula (XI-1) relative to the total mass ofthe liquid crystal composition of the present invention is preferably 1%by mass or more and 20% by mass or less, more preferably 3% by mass ormore and 20% by mass or less, even more preferably 4% by mass or moreand 20% by mass or less, still more preferably 6% by mass or more and15% by mass or less, and particularly preferably 9% by mass or more and12% by mass or less.

Further, preferred examples of the compound represented by the generalformula (XI-1) and used in the liquid crystal composition of the presentinvention include compounds represented by formula (45.1) to formula(45.4), and particularly compounds represented by formula (45.2) toformula (45.4) are preferably contained, and a compound represented byformula (45.2) is more preferably contained.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by theformula (45.2) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 1% by mass or moreand 25% by mass or less, more preferably 2% by mass or more and 20% bymass or less, still more preferably 3% by mass or more and 15% by massor less, particularly preferably 4% by mass or more and 10% by mass orless, and most preferably 4% by mass or more and 5% by mass or less.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by theformula (45.3) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 1% by mass or moreand 25% by mass or less, more preferably 3% by mass or more and 20% bymass or less, still more preferably 3% by mass or more and 15% by massor less, and particularly preferably 3% by mass or more and 10% by massor less.

Examples of the content within the particularly preferred range include3% by mass or more and 6% by mass or less, 7% by mass or more and 10% bymass or less, 5% by mass or more and 8% by mass or less, and 6% by massor more and 7% by mass or less.

In the liquid crystal composition of the present invention, in view ofsolubility at a low temperature, transition temperature, electricreliability, etc., the content of the compound represented by theformula (45.4) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 1% by mass or moreand 25% by mass or less, more preferably 2% by mass or more and 20% bymass or less, still more preferably 3% by mass or more and 15% by massor less, particularly preferably 3% by mass or more and 10% by mass orless, and most preferably 3% by mass or more and 5% by mass or less.

Further, the compound represented by the general formula (XI) and usedin the liquid crystal composition of the present invention is preferablya compound represented by general formula (XI-2).

(In the formula, R¹¹⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (XI-2) can beproperly used in combination according to each embodiment in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1;according to another embodiment of the present invention, the number ofthe types is 2; and according to a further embodiment, the number of thetypes is 3 or more.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of the compound represented bythe general formula (XI-2) relative to the total mass of the liquidcrystal composition of the present invention is preferably 1% by mass ormore and 20% by mass or less, more preferably 3% by mass or more and 20%by mass or less, even more preferably 4% by mass or more and 20% by massor less, still more preferably 6% by mass or more and 15% by mass orless, and particularly preferably 9% by mass or more and 12% by mass orless.

Further, preferred examples of the compound represented by the generalformula (XI-2) and used in the liquid crystal composition of the presentinvention include compounds represented by formula (45.11) to formula(45.14), and particularly compounds represented by formula (45.12) toformula (45.14) are preferably contained, and a compound represented byformula (45.12) is more preferably contained.

Further, the compound represented by the general formula (X) ispreferably a compound selected from a group represented by generalformula (XII).

(In the formula, X¹²¹ to X¹²⁶ each independently represent a fluorineatom or a hydrogen atom, R¹²⁰ represents an alkyl group having 1 to 5carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxygroup having 1 to 4 carbon atoms, and Y¹² represents a fluorine atom or—OCF₃.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (XII) arepreferably used alone or in combination of two to three or more and morepreferably used alone or in combination of two to four or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

Further, the compound represented by the general formula (XII) and usedin the liquid crystal composition of the present invention is preferablya compound represented by general formula (XII-1).

(In the formula, R¹²⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (XII-1) arepreferably used alone or in combination of two or more and morepreferably used alone or in combination of two to three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (XII-1) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 1% by mass or moreand 15% by mass or less, more preferably 2% by mass or more and 10% bymass or less, still more preferably 3% by mass or more and 8% by mass orless, and particularly preferably 4% by mass or more and 6% by mass orless.

Further, preferred examples of the compound represented by the generalformula (XII-1) and used in the liquid crystal composition of thepresent invention include compounds represented by formula (46.1) toformula (46.4), and particularly compounds represented by formula (46.2)to formula (46.4) are preferably contained.

Further, the compound represented by the general formula (XII) ispreferably a compound represented by general formula (XII-2).

(In the formula, R¹²⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

Compounds which can be combined are not particularly limited, but aplurality of compounds represented by the general formula (XII-2) arepreferably used alone or in combination of two or more and morepreferably used alone or in combination of two to three or more in viewof solubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of a compound represented by thegeneral formula (XII-2) relative to the total mass of the liquid crystalcomposition of the present invention is preferably 1% by mass or moreand 20% by mass or less, more preferably 3% by mass or more and 20% bymass or less, even more preferably 4% by mass or more and 17% by mass orless, still more preferably 6% by mass or more and 15% by mass or less,and particularly preferably 9% by mass or more and 13% by mass or less.

Further, preferred examples of the compound represented by the generalformula (XII-2) and used in the liquid crystal composition of thepresent invention include compounds represented by formula (47.1) toformula (47.4), and particularly compounds represented by formula (47.2)to formula (47.4) are preferably contained.

Further, the compound represented by the general formula (M) ispreferably a compound selected from a compound group represented bygeneral formula (XIII).

(In the formula, X¹³¹ to X¹³⁵ each independently represent a fluorineatom or a hydrogen atom, R¹³⁰ represents an alkyl group having 1 to 5carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxygroup having 1 to 4 carbon atoms, and Y¹³ represents a fluorine atom or—OCF₃.)

The types of compounds which can be combined are not particularlylimited, but preferably one or two, more preferably one to three, andstill more preferably one to four of a plurality of compoundsrepresented by the general formula (XIII) are contained.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of a compound represented by the general formula (XIII) hasupper limit and lower limit values according to each embodiment.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 2% to 30% by mass; according toanother embodiment, the content of the compound is 4% to 30% by mass;according to still another embodiment, the content of the compound is 5%to 30% by mass; according to a further embodiment, the content of thecompound is 7% to 30% by mass; according to a further embodiment, thecontent of the compound is 9% to 30% by mass; according to a furtherembodiment, the content of the compound is 11% to 30% by mass; accordingto a further embodiment, the content of the compound is 13% to 30% bymass; according to a further embodiment, the content of the compound is14% to 30% by mass; according to a further embodiment, the content ofthe compound is 16% to 30% by mass; and according to a furtherembodiment, the content of the compound is 20% to 30% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 2% to 30% bymass; according to another embodiment, the content of the compound is 2%to 25% by mass; according to still another embodiment, the content ofthe compound is 2% to 20% by mass; according to a further embodiment,the content of the compound is 2% to 15% by mass; according to a furtherembodiment, the content of the compound is 2% to 10% by mass; andaccording to a further embodiment, the content of the compound is 2% to5% by mass.

When the liquid crystal composition of the present invention is used fora liquid crystal display device having a small cell gap, it is desiredto slightly increase the content of the compound represented by thegeneral formula (XIII). When the liquid crystal composition of thepresent invention is used for a liquid crystal display device having alow drive voltage, it is desired to slightly increase the content of thecompound represented by the general formula (XIII). When the liquidcrystal composition of the present invention is used for a liquidcrystal display device used in a low-temperature environment, it isdesired to slightly decrease the content of the compound represented bythe general formula (XIII). When the liquid crystal composition of thepresent invention is used for a liquid crystal display device havingfast response, it is desired to slightly decrease the content of thecompound represented by the general formula (XIII).

Further, the compound represented by the general formula (XIII) ispreferably a compound represented by general formula (XIII-1).

(In the formula, R¹³⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The content of the compound represented by the general formula (XIII-1)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 1% by mass or more and 25% by mass orless, more preferably 3% by mass or more and 25% by mass or less, stillmore preferably 5% by mass or more and 20% by mass or less, andparticularly preferably 10% by mass or more and 15% by mass or less.

Further, preferred examples of the compound represented by the generalformula (XIII-1) include compounds represented by formula (48.1) toformula (48.4), and particularly a compound represented by formula(48.2) is preferred.

Further, the compound represented by the general formula (XIII) ispreferably a compound represented by general formula (XIII-2).

(In the formula, R¹³⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but at least one of a plurality of compounds represented by thegeneral formula (XIII-2) is preferably contained.

The content of the compound represented by the general formula (XIII-2)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 5% by mass or more and 25% by mass orless, more preferably 6% by mass or more and 25% by mass or less, stillmore preferably 8% by mass or more and 20% by mass or less, andparticularly preferably 10% by mass or more and 15% by mass or less.

Further, preferred examples of the compound represented by the generalformula (XIII-2) include compounds represented by formula (49.1) toformula (49.4), and particularly a compound represented by formula(49.2) is preferred.

Further, the compound represented by the general formula (XIII) ispreferably a compound represented by general formula (XIII-3).

(In the formula, R¹³⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

The types of compounds which can be combined are not particularlylimited, but preferably one or two of a plurality of compoundsrepresented by the general formula (XIII-3) is preferably contained.

The content of the compound represented by the general formula (XIII-3)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 2% by mass or more and 20% by mass orless, more preferably 4% by mass or more and 20% by mass or less, stillmore preferably 9% by mass or more and 17% by mass or less, andparticularly preferably 11% by mass or more and 14% by mass or less.

Further, preferred examples of the compound represented by the generalformula (XIII-3) include compounds represented by formula (50.1) toformula (50.4), and particularly a compound represented by formula(50.1) or formula (50.2) is preferred.

The compound represented by the general formula (M) is preferably acompound selected from a compound group represented by general formula(XIV). However, compounds represented by the general formula (i) areexcluded.

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 7 carbonatoms, an alkenyl group having 2 to 7 carbon atoms, or an alkoxy grouphaving 1 to 7 carbon atoms, X¹⁴¹ to X¹⁴⁴ each independently represent afluorine atom or a hydrogen atom, Y¹⁴ represents a fluorine atom, achlorine atom, or —OCF₃, Q¹⁴ represents a single bond, —COO—, or —CF₂O—,and m¹⁴ represents 0 or 1.)

The types of compounds which can be combined are not limited, but aplurality of compounds represented by the general formula (XIV) can beproperly used in combination according to each embodiment in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to another embodiment of the present invention, the number ofthe types is 2. According to still another embodiment of the presentinvention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4.According to a further embodiment of the present invention, the numberof the types is 5. According to a further embodiment of the presentinvention, the number of the types is 6 or more.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of a compound represented by the general formula (XIV) has anupper limit value and a lower limit value according to each embodiment.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 40% by mass; according toanother embodiment, the content of the compound is 7% to 40% by mass;according to still another embodiment, the content of the compound is 8%to 40% by mass; according to a further embodiment, the content of thecompound is 11% to 40% by mass; according to a further embodiment, thecontent of the compound is 12% to 40% by mass; according to a furtherembodiment, the content of the compound is 16% to 40% by mass; accordingto a further embodiment, the content of the compound is 18% to 40% bymass; according to a further embodiment, the content of the compound is19% to 40% by mass; according to a further embodiment, the content ofthe compound is 22% to 40% by mass; and according to a furtherembodiment, the content of the compound is 25% to 40% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 3% to 40% bymass; according to another embodiment, the content of the compound is 3%to 35% by mass; according to still another embodiment, the content ofthe compound is 3% to 30% by mass; according to a further embodiment,the content of the compound is 3% to 25% by mass; according to a furtherembodiment, the content of the compound is 3% to 20% by mass; andaccording to a further embodiment, the content of the compound is 3% to15% by mass.

When the liquid crystal composition of the present invention is used fora liquid crystal display device having a low drive voltage, it isdesired to slightly increase the content of the compound represented bythe general formula (XIV). When the liquid crystal composition of thepresent invention is used for a liquid crystal display device havingfast response, it is desired to slightly decrease the content of thecompound represented by the general formula (XIV).

Further, the compound represented by the general formula (XIV) ispreferably a compound represented by general formula (XIV-1).

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 7 carbonatoms, an alkenyl group having 2 to 7 carbon atoms, or an alkoxy grouphaving 1 to 7 carbon atoms, and Y¹⁴ represents a fluorine atom, achlorine atom, or —OCF₃.)

The type of compounds which can be combined are not limited, but aplurality of compounds represented by the general formula (XIV-1) can beproperly used alone or in combination of two to three in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc.

Further, the compound represented by the general formula (XIV-1) ispreferably a compound represented by general formula (XIV-1-1).

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 7 carbonatoms, an alkenyl group having 2 to 7 carbon atoms, or an alkoxy grouphaving 1 to 7 carbon atoms.)

The content of the compound represented by the general formula (XIV-1)relative to the total mass of the liquid crystal composition of thepresent invention is preferably 2% by mass or more, more preferably 4%by mass or more, even more preferably 7% by mass or more, still morepreferably 10% by mass or more, and particularly preferably 18% by massor more. In addition, in view of solubility at a low temperature,transition temperature, electric reliability, etc., the maximum ratio ispreferably limited to 30% by mass or less, more preferably 27% by massor less, still more preferably 24% by mass or less, and particularlypreferably less than 21% by mass.

Further, preferred examples of the compound represented by the generalformula (XIV-1-1) include compounds represented by formula (51.1) toformula (51.4), and particularly a compound represented by formula(51.1) is preferred.

Further, the compound represented by the general formula (XIV-1) ispreferably a compound represented by general formula (XIV-1-2).

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 7 carbonatoms, an alkenyl group having 2 to 7 carbon atoms, or an alkoxy grouphaving 1 to 7 carbon atoms.)

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of the compound represented bythe general formula (XIV-1-2) relative to the total mass of the liquidcrystal composition of the present invention is preferably 1% by mass ormore and 15% by mass or less, more preferably 3% by mass or more and 13%by mass or less, still more preferably 5% by mass or more and 11% bymass or less, and particularly preferably 7% by mass or more and 9% bymass or less.

Further, preferred examples of the compound represented by the generalformula (XIV-1-2) include compounds represented by formula (52.1) toformula (52.4), and particularly a compound represented by formula(52.4) is preferably contained.

Further, the compound represented by the general formula (XIV) ispreferably a compound represented by general formula (XIV-2). However,compounds represented by the general formula (i) are excluded.

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms, X¹⁴¹ to X¹⁴⁴ each independently represent afluorine atom or a hydrogen atom, and Y¹⁴ represents a fluorine atom, achlorine atom, or —OCF₃.)

The type of compounds which can be combined are not limited, but aplurality of compounds represented by the general formula (XIV-2) can beproperly used in combination according to each embodiment in view ofsolubility at a low temperature, transition temperature, electricreliability, birefringence, etc. For example, according to an embodimentof the present invention, the number of the type of compound used is 1.According to another embodiment of the present invention, the number ofthe types is 2. According to still another embodiment of the presentinvention, the number of the types is 3. According to a furtherembodiment of the present invention, the number of the types is 4.According to a further embodiment of the present invention, the numberof the types is 5 or more.

In view of characteristics such as solubility at a low temperature,transition temperature, electric reliability, birefringence, etc., thecontent of a compound represented by the general formula (XIV-2) has anupper limit value and a lower limit value according to each embodiment.

For example, according to an embodiment of the present invention, thecontent of the compound relative to the total mass of the liquid crystalcomposition of the present invention is 3% to 40% by mass; according toanother embodiment, the content of the compound is 7% to 40% by mass;according to still another embodiment, the content of the compound is 8%to 40% by mass; according to a further embodiment, the content of thecompound is 10% to 40% by mass; according to a further embodiment, thecontent of the compound is 11% to 40% by mass; according to a furtherembodiment, the content of the compound is 12% to 40% by mass; accordingto a further embodiment, the content of the compound is 18% to 40% bymass; according to a further embodiment, the content of the compound is19% to 40% by mass; according to a further embodiment, the content ofthe compound is 21% to 40% by mass; and according to a furtherembodiment, the content of the compound is 22% to 40% by mass.

Also, for example, according to an embodiment of the present invention,the content of the compound relative to the total mass is 3% to 40% bymass; according to another embodiment, the content of the compound is 3%to 35% by mass; according to still another embodiment, the content ofthe compound is 3% to 25% by mass; according to a further embodiment,the content of the compound is 3% to 20% by mass; according to a furtherembodiment, the content of the compound is 3% to 15% by mass; andaccording to a further embodiment, the content of the compound is 3% to10% by mass.

When the liquid crystal composition of the present invention is used fora liquid crystal display device having a low drive voltage, it isdesired to slightly increase the content of the compound represented bythe general formula (XIV-2). When the liquid crystal composition of thepresent invention is used for a liquid crystal display device havingfast response, it is desired to slightly decrease the content of thecompound represented by the general formula (XIV-2).

Further, the compound represented by the general formula (XIV-2) ispreferably a compound represented by general formula (XIV-2-1).

(In the formula, R¹⁴⁰ represents an alkyl group having 1 to 5 carbonatoms, an alkenyl group having 2 to 5 carbon atoms, or an alkoxy grouphaving 1 to 4 carbon atoms.)

In view of solubility at a low temperature, transition temperature,electric reliability, etc., the content of the compound represented bythe general formula (XIV-2-1) relative to the total mass of the liquidcrystal composition of the present invention is preferably 1% by mass ormore and 15% by mass or less, more preferably 3% by mass or more and 13%by mass or less, still more preferably 5% by mass or more and 11% bymass or less, and particularly preferably 7% by mass or more and 9% bymass or less.

Further, preferred examples of the compound represented by the generalformula (XIV-2-1) include compounds represented by formula (53.1) toformula (53.4), and particularly a compound represented by formula(53.4) is preferably contained.

Each of the compounds used in the present invention does not have aperoxy acid (—CO—OO—) structure in its molecule. Also, when reliabilityand long-terms stability of the liquid crystal composition are regardedas important, it is desired not to use a compound having a carbonylgroup. In addition, when UV irradiation stability is regarded asimportant, it is desired not to use a compound substituted by a chlorineatom. It is also desired to use only compounds in which all ringstructures in a molecule are six-member rings.

The liquid crystal composition of the present invention preferably doesnot contain a compound having, in its molecule, a structure, such as aperoxy acid (—CO—OO—) structure or the like, in which oxygen atoms arebonded to each other.

When reliability and long-term stability of the liquid crystalcomposition are regarded as important, the content of a compound havinga carbonyl group is preferably 5% by mass or less, more preferably 3% bymass or less, still more preferably 1% by mass or less, and mostpreferably substantially zero, relative to the total mass of thecomposition.

When UV irradiation stability is regarded as important, the content of acompound substituted by a chlorine atom is preferably 15% by mass orless, more preferably 10% by mass or less, still more preferably 5% bymass or less, and most preferably substantially zero, relative to thetotal mass of the composition.

It is desired to increase the content of a compound in which all ringstructures in its molecule are six-member rings, and the content of acompound in which all ring structures in its molecule are six-memberrings is preferably 80% by mass or more, more preferably 90% by mass ormore, and still more preferably 95% by mass or more relative to thetotal mass of the composition, and most preferably the liquid crystalcomposition includes substantially only compounds in which all ringstructures in a molecule are six-member rings.

In order to suppress deterioration due to oxidation of the liquidcrystal composition, it is preferred to decrease the content of acompound having a cyclohexenylene group as a ring structure, and thecontent of a compound having a cyclohexenylene group is preferably 10%by mass or less, more preferably 5% by mass or less, and still morepreferably substantially zero, relative to the total mass of thecomposition.

When improvements in viscosity and Tni are regarded as important, it ispreferred to decrease the content of a compound having, in its molecule,a 2-methylbenzene-1,4-diyl group which may be substituted by a halogenfor a hydrogen atom, and the content of the compound having a2-methylbenzene-1,4-diyl group in its molecule is preferably 10% by massor less, more preferably 5% by mass or less, and still more preferablysubstantially zero, relative to the total mass of the composition.

When the composition according to the first embodiment of the presentinvention contains a compound having as a side chain an alkenyl groupbonded to cyclohexane, the alkenyl group preferably has 2 to 5 carbonatoms, and when the alkenyl group is bonded to benzene, the alkenylgroup preferably has 4 to 5 carbon atoms, and an unsaturated bond of thealkenyl group is preferably not directly bonded to benzene.

The liquid crystal composition of the present invention can contain apolymerizable compound in order to manufacture a liquid crystal displaydevice of a PS mode, a horizontal electric field-type PSA mode, or ahorizontal electric field-type PSVA mode. A photopolymerizable monomersubjected to polymerization that proceeds by energy rays such as lightcan be used as the polymerizable compound, and a polymerizable compoundhaving as a structure a liquid crystal skeleton in which a plurality ofsix-member rings are connected together, for example, a biphenylderivative, a terphenyl derivative, or the like, can be used. Preferredexamples thereof include difunctional monomers represented by generalformula (XX).

(In the formula, X²⁰¹ and X²⁰² each independently represent a hydrogenatom or a methyl group,Sp²⁰¹ and Sp²⁰² each independently represent a single bond, an alkylenegroup having 1 to 8 carbon atoms, or —O—(CH₂)_(s)— (wherein s representsan integer of 2 to 7, and an oxygen atom is bonded to an aromatic ring),Z²⁰¹ represents —OCH₂—, —CH₂O—, —COO—, —OCO—, —CF₂O—, —OCF₂—, —CH₂CH₂—,—CF₂CF₂—, —CH═CH—COO—, —CH═CH—OCO—, —COO—CH═CH—, —OCO—CH═CH—,—COO—CH₂CH₂—, —OCO—CH₂CH₂—, —CH₂CH₂—COO—, —CH₂CH₂—OCO—, —COO—CH₂—,—OCO—CH₂—, —CH₂—COO—, —CH₂—OCO—, —CY¹═CY²—(wherein Y¹ and Y² each independently represent a fluorine atom or ahydrogen atom), —C≡C—, or a single bond,M²⁰¹ represents a 1,4-phenylene group, a trans-1,4-cyclohexylene group,or a single bond, and all 1,4-phenylene groups in the formula may have afluorine atom substituted for any desired hydrogen atom.)

Either a diacrylate derivative in which X²⁰¹ and X²⁰² both representhydrogen atoms or a dimethacrylate derivative in which X²⁰¹ and X²⁰²both represent methyl groups is preferred, and a compound in which oneof X²⁰¹ and X²⁰² represents a hydrogen atom, and the other represents amethyl group is also preferred. Among these compounds, the diacrylatederivative has the highest polymerization rate, the dimethacrylatederivative has a lower polymerization rate, and an asymmetric compoundhas a medium polymerization rate between them. A preferred form can beused according to application. The dimethacrylate derivative isparticularly preferred for a PSA display device.

Sp²⁰¹ and Sp²⁰² each independently represent a single bond, an alkylenegroup having 1 to 8 carbon atoms, or —O—(CH₂)_(s)—, but at least one ofSp²⁰¹ and Sp²⁰² is preferably a single bond for a PSA display device.Specifically, a compound in which Sp²⁰¹ and Sp²⁰² both represent singlebonds or a form in which one represents a single bond, and the otherrepresents an alkylene group having 1 to 8 carbon atoms, or—O—(CH₂)_(s)— is preferred. In this case, a 1-4 alkyl group ispreferred, and s is preferably 1 to 4.

Z²⁰¹ is preferably —OCH₂—, —CH₂O—, —COO—, —OCO—, —CF₂O—, —OCF₂—,—CH₂CH₂—, —CF₂CF₂—, or a single bond, more preferably —COO—, —OCO—, or asingle bond, and particularly preferably a single bond.

M²⁰¹ represents a 1,4-phenylene group in which any hydrogen atom may besubstituted by a fluorine atom, a trans-1,4-cyclohexylene group, or asingle bond, but a 1,4-phenylene group or a single bond is preferred.When C represents a ring structure other than a single bond, Z²⁰¹ isalso preferably a linkage group other than a single bond, and when M²⁰¹is a single bond, Z²⁰¹ is preferably a single bond.

In view of the above, specifically, a ring structure between Sp²⁰¹ andSp²⁰² in the general formula (XX) is preferably a structure describedbelow.

In the general formula (XX), when M²⁰¹ represents a single bond, and thering structure includes two rings, formula (XXa-1) to formula (XXa-5)are preferred, formula (XXa-1) to formula (XXa-3) are more preferred,and formula (XXa-1) is particularly preferred.

(In the formulae, each end is bonded to Sp²⁰¹ or Sp²⁰².)

A polymerizable compound having such a skeleton has, afterpolymerization, alignment regulating force optimum for a PSA-mode liquidcrystal display device, and thus a good alignment state can be achieved,thereby suppressing display unevenness or causing no display unevenness.

In view of the above, polymerizable monomers of general formula (XX-1)to general formula (XX-4) are particularly preferred, and generalformula (XX-2) is most preferred.

(In the formulae, Sp²⁰ represents an alkylene group having 2 to 5 carbonatoms.)

When the monomer is added to the liquid crystal composition of thepresent invention, polymerization proceeds even in the absence of apolymerization initiator, but the polymerization initiator may be addedfor accelerating polymerization. Examples of the polymerizationinitiator include benzoin ethers, benzophenones, acetophenones,benzylketals, acylphosphine oxides, and the like.

The liquid crystal composition of the present invention can furthercontain a compound represented by general formula (Q).

(In the formula, R^(Q) represents a linear alkyl or branched alkyl grouphaving 1 to 22 carbon atoms, one or two or more CH₂ groups in the alkylgroup may be substituted by —O—, —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—,—CF₂O—, or OCF₂— so that oxygen atoms do not directly adjacent to eachother, and M^(Q) represents a trans-1,4-cyclohexylene group, a1,4-phenylene group, or a single bond.)

R^(Q) represents a linear alkyl or branched alkyl group having 1 to 22carbon atoms, and one or two or more CH₂ groups in the alkyl group maybe substituted by —O—, —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—, —CF₂O—, orOCF₂— so that oxygen atoms do not directly adjacent to each other.However, a linear alkyl group having 1 to 10 carbon atoms, a linearalkoxy group, a linear alkyl group in which one CH₂ group is substitutedby —OCO— or —COO—, a branched alkyl group, a branched alkoxy group, anda branched alkyl group in which one CH₂ group is substituted by —OCO— or—COO— are preferred, and a linear alkyl group having 1 to 20 carbonatoms, a linear alkyl group in which one CH₂ group is substituted by—OCO— or —COO—, a branched alkyl group, a branched alkoxy group, and abranched alkyl group in which one CH₂ group is substituted by —OCO— or—COO— are more preferred. M^(Q) represents a trans-1,4-cyclohexylenegroup, a 1,4-phenylene group, or a single bond, but atrans-1,4-cyclohexylene group or a 1,4-phenylene group is preferred.

Preferred examples of the compound represented by the general formula(Q) include compounds represented by general formula (Q-a) to generalformula (Q-d) below.

In the formulae, R^(Q1) is preferably a linear alkyl or branched alkylgroup having 1 to 10 carbon atoms, R^(Q2) is preferably a linear alkylor branched alkyl group having 1 to 20 carbon atoms, R^(Q3) ispreferably a linear alkyl or branched alkyl group having 1 to 8 carbonatoms, a linear alkoxy group, or a branched alkoxy group, L^(Q) ispreferably a linear alkylene or branched alkylene group having 1 to 8carbon atoms. Among compounds represented by the general formula (Q-a)to the general formula (Q-d), compounds represented by the generalformula (Q-c) and the general formula (Q-d) are more preferred.

The liquid crystal composition of the present invention preferablycontains one or two compounds and more preferably one to five compoundsrepresented by the general formula (Q), and the content thereof ispreferably 0.001% to 1% by mass, more preferably 0.001% to 0.1% by mass,and particularly preferably 0.001% to 0.05% by mass.

<Liquid Crystal Display Device>

The liquid crystal composition containing the polymerizable compound ofthe present invention is imparted with a liquid crystal alignmentability when the polymerizable compound contained is polymerized byirradiation with ultraviolet light, and is used for a liquid crystaldisplay device in which a quantity of light transmitted is controlled byusing birefringence of the liquid crystal composition. The liquidcrystal composition is useful for liquid crystal display devices, suchas ECB-LCD, VA-LCD, FFS-LCD, AM-LCD (active matrix liquid crystaldisplay device), TN (nematic liquid crystal display device), STN-LCD(super twisted nematic liquid crystal display device), OCB-LCD, andIPS-LCD (in-plane switching liquid crystal display device), particularlyuseful for AM-LCD, and can be used for transmissive or reflective liquidcrystal display devices.

Two substrates of a liquid crystal cell used in a liquid crystal displaydevice can be formed by using a transparent material with flexibility,such as glass or plastic, and one of the two substrates may be made ofan opaque material such as silicon or the like. A transparent substrateincluding a transparent electrode layer can be formed by, for example,sputtering indium tin oxide (ITO) on a transparent substrate such as aglass plate or the like.

A color filter can be formed by, for example, a pigment dispersionmethod, a printing method, an electrodeposition method, a dyeing method,or the like. The method for forming a color filter by the pigmentdispersion method is described as an example. A curable coloredcomposition for a color filter is applied on the transparent substrate,patterned, and then cured by heating or light irradiation. This processis performed for each of the three colors of red, green, and blue,thereby forming a pixel portion for a color filter. In addition, a pixelelectrode provided with an active element such as TFT, a thin-filmdiode, or the like may be installed on the substrate.

The substrates are opposed to each other so that the transparentelectrode layers face inward. In this case, the gap between thesubstrates may be adjusted through spacers. The resulting light controllayer is preferably adjusted to have a thickness of 1 to 100 μm. Thethickness is more preferably 1.5 to 10 μm, and when a polarizing plateis used, the product of refractive index anisotropy Δn of a liquidcrystal and cell thickness d is preferably adjusted to maximizecontrast. When two polarizing plates are used, an angle of view andcontrast can be improved by adjusting the polarizing axis of each of thepolarizing plates. Further, a retardation film can be used for wideningthe angle of view. Examples of the spacers include glass particles,plastic particles, alumina particles, columnar spacers made of aphotoresist material, and the like. Then, a sealing agent such as anepoxy-based heat-curable composition or the like is screen-printed in aform having a liquid crystal inlet on each of the substrates, thesubstrates are bonded together, and then the sealing agent is thermallycured by heating.

A usual vacuum injection method or ODF method can be used as a methodfor holding the liquid crystal composition containing the polymerizablecompound between the substrates. However, the vacuum injection methodhas the problem of leaving injection marks, instead of causing droppingmarks. The present invention can preferably use the ODF method in aprocess for manufacturing a liquid crystal display device. In theprocess for manufacturing a liquid crystal display device using the ODFmethod, the liquid crystal display device can be manufactured byapplying an epoxy-based light/heat curable sealing agent on a substrateof either a back plane or a front plane by using a dispenser to draw aclosed loop bank-like shape, dropping a predetermined amount of theliquid crystal composition in the shape under deaeration, and thenbonding together the front plane and the back plane are bonded. Theliquid crystal composition of the present invention can be stablydropped in the ODF step and thus can be preferably used.

Since an appropriate polymerization rate is desired for achieving goodliquid crystal-aligning performance, a preferred method of polymerizingthe polymerizable compound is a polymerization method in which thecompound is polymerized by irradiation with one or combination of two ormore of active energy rays such as ultraviolet light, electron beams,and the like, or by sequential irradiation with these active energyrays. When ultraviolet light is used, either a polarized light source oran unpolarized light source may be used. When the liquid crystalcomposition containing the polymerizable compound is polymerized in astate of being held between the two substrates, at least the substrateon the irradiation surface side must be imparted with propertransparency to the active energy rays. In addition, another method maybe used, in which only a specified portion is polymerized by using amask during light irradiation, and then the alignment state of anunpolymerized portion is changed by changing a condition such as anelectric field, a magnetic field, or a temperature, followed by furtherpolymerization by irradiation with active energy rays. In particular,ultraviolet exposure is preferably performed by applying analternating-current electric field to the liquid crystal compositioncontaining the polymerizable compound. The alternating-current electricfield is preferably applied with an alternating current at a frequencyof 10 Hz to 10 kHz, more preferably a frequency of 60 Hz to 10 kHz, anda voltage selected depending on a desired pre-tilt angle of the liquidcrystal display device. That is, the pre-tilt angle of the liquidcrystal display device can be controlled by the voltage applied. In ahorizontal electric field-type MVA-mode liquid crystal display device,the pre-tilt angle is preferably controlled to 80 degrees to 89.9degrees from the viewpoint of alignment stability and contrast.

The temperature during irradiation preferably falls in a temperaturerange in which the liquid crystal state of the liquid crystalcomposition of the present invention can be maintained. Polymerizationis preferably performed at a temperature close to room temperature,typically a temperature of 15° C. to 35° C. A metal halide lamp, ahigh-pressure mercury lamp, a superhigh-pressure mercury lamp, or thelike can be used as a lamp which generates ultraviolet light. Withrespect to a wavelength of irradiating ultraviolet light, irradiationwith ultraviolet light within a wavelength region which is not anabsorption wavelength region of the liquid crystal composition ispreferred, and if required, ultraviolet light is preferably partiallycut off. The intensity of irradiating ultraviolet light is preferably0.1 mW/cm² to 100 W/cm² and more preferably 2 mW/cm² to 50 W/cm². Aquantity of irradiating ultraviolet light energy can be appropriatelyadjusted, but it is preferably 10 mJ/cm² to 500 J/cm², and morepreferably 100 mJ/cm² to 200 J/cm². During ultraviolet irradiation, theintensity may be changed. The time required for ultraviolet irradiationis appropriately selected according to the intensity of irradiatingultraviolet light, but is preferably 10 seconds to 3600 seconds and morepreferably 10 seconds to 600 seconds.

The liquid crystal display device using the liquid crystal compositionof the present invention satisfies both fast response and thesuppression of display defects and is useful, particularly useful forliquid crystal display devices for active matrix driving, and can beused for liquid crystal display devices for a VA mode, a PSVA mode, aPAS-mode, an IPS (in-plane switching) mode, a FSS (fringe fieldswitching) mode, or an ECB mode.

A liquid crystal display device (liquid crystal display) according to apreferred embodiment of the present invention is described in detailbelow with reference to the drawings.

FIG. 1 is a sectional view showing a liquid crystal display deviceincluding two opposed substrates, a sealing material provided betweenthe substrates, and a liquid crystal sealed in a sealing regionsurrounded by the sealed material.

Specifically, the liquid crystal display device shown has a specifiedform in which a back plane formed by providing thereon a TFT layer 102and a pixel electrode 103 on a first substrate 100 and further providinga passivation film 104 and a first alignment film 105 is opposed to afront plane formed by providing on a second substrate 200 a black matrix202, a color filter 203, a planarization film (overcoat film) 201, and atransparent electrode 204 and then providing a second alignment film 205thereon. Further, a sealing material 301 is provided between thesubstrates, a liquid crystal layer 303 is provided to be sealed in asealed region surrounded by the sealing material, and projections(columnar spacers) 302 and 304 are provided on the substrate surface incontact with the sealing material 301.

The material of the first substrate or the second substrate is notparticularly limited as long as it is substantially transparent, andglass, ceramics, plastics, and the like can be used. Materials which canbe used for a plastic substrate include cellulose derivatives such ascellulose, triacetyl cellulose, diacetyl cellulose, and the like;polycycloolefin derivatives; polyesters such as polyethyleneterephthalate, polyethylene naphthalate, and the like; polyolefins suchas polypropylene, polyethylene, and the like; polycarbonate, polyvinylalcohol, polyvinyl chloride, polyvinylidene chloride, polyamide,polyimide, polyimide-amide, polystyrene, polyacrylate, polymethylmethacrylate, polyether sulfone, polyarylate, inorganic-organiccomposite materials such as glass fiber-epoxy resin, glass fiber-acrylicresin, and the like.

When a plastic substrate is used, a barrier film is preferably provided.The function of the barrier film is to decrease the moisturepermeability possessed by the plastic substrate to improve thereliability of electric characteristics of the liquid crystal displaydevice. The barrier film is not particularly limited as long as it hashigh transparency and low water-vapor permeability, and a thin filmformed by vapor deposition, sputtering, or chemical vapor deposition(CVD method) using an inorganic material such as silicon dioxide or thelike is generally used.

In the present invention, the materials used for the first substrate andthe second substrate are not particularly limited and may be the same ordifferent. A glass substrate is preferred because the liquid crystaldisplay device having excellent heat resistance and dimensionalstability can be manufactured. Also, a plastic substrate is preferredbecause it is suitable for a manufacturing method by a roll-to-rollmethod and also suitable for weight lightening or flexibilizing. Inaddition, for the purpose of imparting flatness and heat resistance,good results can be obtained by a combination of a plastic substrate anda glass substrate.

In examples described below, a substrate is used as a material of thefirst substrate 100 or the second substrate 200.

The back plane includes the TFT layer 102 and the pixel electrode 103provided on the first substrate 100. These are produced by a usual arrayprocess. The passivation film 104 and the first alignment film 105 areprovided thereon to produce the back plane.

The passivation film 104 (also referred to as the inorganic protectivefilm) is a film for protecting the TFT layer, and a nitride film(SiN_(x)), an oxide film (SiO_(x)), or the like is generally formed by achemical vapor deposition (CVD) technique or the like.

The first alignment film 105 is a film having the function to align aliquid crystal, and a polymer material such as polyimide is generallyused in many cases. An alignment agent solution including a polymermaterial and a solvent is used as a coating solution. The alignment filmmay inhibit adhesive force with the sealing material, and is thus formedby pattern application within the sealed region. The application isperformed by using a printing method such as a flexographic printingmethod or a droplet discharge method such as ink jet. The appliedalignment agent solution is pre-dried to evaporate the solvent, and thencross-linked and cured by baking. Then, alignment treatment is performedfor causing an alignment function.

The alignment treatment is generally performed by a rubbing method. Thepolymer film formed as described above is rubbed in one direction with arubbing cloth composed of fibers such as rayon to cause a liquid crystalaligning function.

Also, an optical alignment method may be used. The optical alignmentmethod is a method of producing the alignment function by irradiating analignment film containing an organic material having photosensitivitywith polarized light without causing flaws or dust on the substrate dueto rubbing. An example of the organic material used in the opticalalignment method is a material containing a dichroic dye. A dye whichcan be used as the dichroic dye is a dye having a group (hereinafterabbreviated as an “optical alignment group”) which producesphotoreaction serving as an origin of the liquid crystal alignmentfunction, such as molecular alignment induction or isomerizationreaction by a Weigert effect due to photodichroism (for example, anazobenzene group), dimerization reaction (for example, a cinnamoylgroup), photo-crosslinking reaction (for example, a benzophenone group),or photodecomposition reaction (for example, a polyimide group). Theapplied alignment agent solution is pre-dried to evaporate the solventand then irradiated with light (polarized light) having any desiredpolarization to produce an alignment film having the alignment functionin a desired direction.

On the other hand, the front plane includes the black matrix 202, thecolor filter 203, the planarization film 201, the transparent electrode204, and the second alignment film 205 which are provided on the secondsubstrate 200.

The black matrix 202 is formed by, for example, a pigment dispersionmethod. Specifically, a color resin solution containing a black colorantuniformly dispersed therein for forming the black matrix is applied tothe second substrate 200 provided with the barrier film 201 to form acolor layer. Then, the color layer is cured by baking. Then, photoresistis applied to the color layer and then pre-baked. The photoresist isexposed to light through a mask pattern, and then the color layer ispatterned by development. Then, the photoresist layer is removed, andthe color layer is baked to complete the black matrix 202.

Alternatively, a photoresist-type pigment dispersion may be used. Inthis case, the photoresist-type pigment dispersion is applied,pre-baked, and then exposed to light through a mask pattern, and thenthe color layer is patterned by development. Then, the photoresist layeris removed, and the color layer is baked to complete the black matrix202.

The color filter 203 is formed by a pigment dispersion method, anelectrodeposition method, a printing method, or a dyeing method. Forexample, in the pigment dispersion method, a color resin solutioncontaining a (for example, red) pigment uniformly dispersed therein isapplied to the second substrate 200 and cured by baking, and then aphotoresist is applied thereon and pre-baked. The photoresist is exposedto light through a mask pattern and patterned by development. Then, thephotoresist layer is removed, and baking is again performed to completethe (red) color filter 203. The order of the colors to be formed is notparticularly limited. Similarly, a green color filter 203 and a bluecolor filter 203 are formed.

The transparent electrode 204 is provided on the color filter 203 (ifrequired, the overcoat layer (201) is provided on the color filter 203in order to planarize the surface). The transparent electrode 204preferably has as high transmittance as possible and as low electricresistance as possible. The transparent electrode 204 is formed by asputtering method of forming an oxide film such as ITO or the like.

Also, for the purpose of protecting the transparent electrode 204, thepassivation film may be provided on the transparent electrode 204.

The second alignment film 205 is the same as the first alignment film105 described above.

The specific configurations of the back plane and the front plane usedin the present invention are described above, but the present inventionis not limited to the specific configurations, and modification in theconfigurations can be freely made according to a desired liquid crystaldisplay device.

The shape of the columnar spacers is not particularly limited, and thehorizontal section thereof can be formed in any one of various shapessuch as a circular shape, polygonal shapes, e.g., a tetragonal shape,and the like. However, in view of a misalignment margin in a process,the horizontal section particularly preferably has a circular shape or aregular polygonal shape. Also, the projection shape is preferably atruncated conical shape or a truncated pyramidal shape.

The material of the columnar spacers is not particularly limited as longas it is undissolved in the sealing material, the organic solvent usedin the sealing material, or the liquid crystal, but a synthetic resin(curable resin) is preferred from the viewpoint of processing and weightlightening. On the other hand, the projections can be provided on thesurface of the first substrate in contact with the sealing material by aphotolithography method or a droplet discharge method. For this reason,a photocurable resin suitable for the photolithography method or dropletdischarge method is preferably used.

A case where the columnar spacers are formed by the photolithographymethod is described as an example. FIG. 2 is a drawing of an exposurestep using, as a photomask pattern, a pattern for forming columnarspacers on a black matrix.

A resin solution (not containing a colorant) for forming the columnarspacers is applied to the transparent electrode 204 of the front plane.Then, a resin layer 402 is cured by baking. Then, a photoresist isapplied to the resin layer and pre-baked. The photoresist is exposed tolight through a mask pattern 401, and then the resin layer is patternedby development. Then, the photoresist layer is removed, and the resinlayer is baked to complete columnar spacers (302 and 0304 in FIG. 1).

The formation positions of the columnar spacers can be determined todesired positions by the mask pattern. Therefore, both the inside of thesealed region and the outside (sealing material applied portion) of thesealing region of the liquid crystal display device can besimultaneously formed. Also, the columnar spacers are preferably formedat positions on the black matrix so as not to degrade the quality of thesealed region. The columnar spacers formed by the photolithographymethod may be referred to as “column spacers” or “photo-spacers”.

A mixture containing a negative water-soluble resin, such as aPVA-stilbazo photosensitive resin or the like, a polyfunctional acrylicmonomer, an acrylic acid copolymer, a triazole-based initiator, etc. isused as the material of the columnar spacers. Another method uses acolor resin prepared by dispersing a colorant in a polyimide resin. Inthe present invention, the material is not particularly limited, and thespacers can be formed by using a known material according tocompatibility with the liquid crystal and sealing material used.

After the columnar spacers are provided on the surface serving as thesealed region on the front plane as described above, the sealingmaterial (301 in FIG. 1) is applied to the surface of the back planewhich comes in contact with the sealing material.

The material of the sealing material is not particularly limited, and acurable resin composition prepared by adding a polymerization initiatorto an epoxy-based or acrylic photo-curable, heat-curable, orphoto-heat-curable resin is used. Also, in order to control moisturepermeability, elastic modulus, and viscosity, a filler composed of aninorganic or organic substance may be added. Examples of the shape ofthe filler include, but not particularly limited to, a spherical shape,a fibrous shape, an amorphous shape, and the like. Further, a sphericalor fibrous gap material having a monodisperse diameter may be mixed forcontrolling a good cell gap, or a fibrous material which is easilyentangled with projections on the substrate may be mixed for moreenhancing the adhesive force to the substrate. In this case, thediameter of the fibrous material used is preferably about ⅕ to 1/10 orless of the cell gap, and the length of the fibrous material ispreferably shorter than the width of the seal applied.

The material of the fibrous material is not particularly limited as longas a predetermined shape can be formed, and can be properly selectedfrom synthetic fibers such as cellulose, polyamide, polyester, and like,and inorganic materials such as glass, carbon, and the like.

The method for applying the sealing material is a printing method or adispensing method, and the dispensing method is preferred because of asmall amount of the sealing material used. The application position ofthe sealing material is generally a position on the black matrix so asto avoid an adverse effect on the sealed region. In order to form aliquid crystal dropping region in the next step (to avoid leakage of theliquid crystal), the shape of the sealing material applied is aclosed-loop shape.

The liquid crystal is dropped in the closed-loop shape (sealed region)of the front plane to which the sealing material has been applied.Usually, a disperser is used. In order to allow the amount of the liquidcrystal dropped to coincide with the volume of a liquid crystal cell,the amount of the liquid crystal dropped is basically the same as thevolume determined by multiplying the height of the columnar spacers bythe area of the seal applied. In order to optimize a liquid crystalleakage in a cell bonding step and display characteristics, the amountof the liquid crystal dropped may be properly adjusted, or liquidcrystal dropping positions may be dispersed.

Next, the back plane is bonded to the front plane on which the sealingmaterial has been applied, and the liquid crystal has been dropped.Specifically, the front plane and the back plane are attracted to astage having a mechanism of attracting a substrate, such as anelectrostatic chuck, to be arranged at a position (distance) where thesecond alignment film of the front plane faces the first alignment filmof the back plane, and the sealing agent does not contact the othersubstrate. In this state, the pressure in the system is reduced. Afterthe completion of pressure reduction, the positions of both substratesare adjusted (alignment operation) while the bonding position betweenthe front plane and the back plane is confirmed. After the adjustment ofthe bonding position is completed, the substrates are brought near toeach other to a position where the sealing material on the front planeis in contact with the back plane. In this state, the system is filledwith inert gas to return the pressure to atmospheric pressure whilegradually releasing the reduced pressure. In this case, the front planeand the back plane are bonded together by the atmospheric pressure toform a cell gap corresponding to the height of the columnar spacers. Inthis state, the sealing material is cured by irradiation withultraviolet light to form a liquid crystal cell. Then, in some cases, aheating step is added to accelerate curing of the sealing material. Inorder to enhance adhesion of the sealing material and improvereliability of electric characteristics, the heating step is oftenadded.

EXAMPLES

The present invention is described in further detail below by way ofexamples, but the present invention is not limited to these examples. Inthe examples and comparative examples below, “%” in a compositionrepresents “% by mass”.

The characteristics measured in the examples are as follows.

Tni: nematic-isotropic liquid phase transition temperature (° C.)

Δn: refractive index anisotropy at 295K (sometimes called birefringence)

Δ∈: dielectric anisotropy at 295K

η: viscosity at 295K (mPa·s)

γ1: rotational viscosity at 295K (mPa·s)

Initial voltage holding ratio (initial VHR); voltage holding ratio (%)at 50° C. under the conditions of a frequency of 60 Hz and an appliedvoltage of 4 V

Voltage holding ratio after heating (VHR after heating); voltage holdingratio (%) measured under the same conditions as for initial VHR afterheating in an atmosphere of 150° C. for 1 hour

<Evaluation of Image Sticking>

Image sticking of a liquid crystal display device was evaluated bydisplay of a predetermined fixed pattern within a display area for 1440hours and then uniform display over the entire screen to visuallyobserve the level of residual image of the fixed pattern based on thefollowing four levels:

A: No residual image

B: Slight residual image at an allowable level

C: Residual image at an unallowable level

D: Significant residual image

<Evaluation of Volatility (Contamination of Manufacturing Apparatus)>

Volatility of a liquid crystal material was evaluated by observingoperating conditions of a vacuum stirring-defoaming mixer under lightingwith a stroboscope and visually observing foaming of the liquid crystalmaterial. Specifically, 0.15 kg of the liquid crystal material wasplaced in a dedicated vessel of the vacuum stirring-defoaming mixer witha volume of 0.5 L, and the vacuum stirring defoaming mixer was operatedat a revolution speed of 15 S⁻¹ and a rotation speed of 7.5 S⁻¹ underdeaeration at 4 kPa to determine a time required until the start offoaming based on the following four levels.

A: Three minutes or more were required until foaming, causing the lowpossibility of apparatus contamination by evaporation

B: One minute or more and less than 3 minutes were required untilfoaming, causing the possibility of slight apparatus contamination byevaporation

C: Thirty seconds or more and less than 1 minute were required untilfoaming, causing the occurrence of apparatus contamination byevaporation

D: Less than thirty seconds were required until foaming, causing thepossibility of significant apparatus contamination by evaporation

<Evaluation of Process Adaptability>

Process adaptability was evaluated by, in the ODF process, dropping 40pL of liquid crystal each 100000 times using a constant-volume measuringpump to measure a change in amount of the liquid crystal dropped 200times during each of 0 to 200 times, 201 to 400 times, 401 to 600 times,. . . 99801 to 100000 times dropping based on the following four levels:

A: Very small change (enabling stable manufacture of a liquid crystaldisplay device)

B: Slight change at an allowable level

C: Change at an unallowable level (degrading yield due to the occurrenceof spots)

D: Significant change (causing liquid crystal leakage or vacuum foaming)

<Evaluation of Solubility at Low Temperature>

Solubility at a low temperature was evaluated by, after preparing aliquid crystal composition, weighing 0.5 g of the liquid crystalcomposition in a 1-mL sample bottle, and continuously changing thetemperature in a cycle of −20° C. (kept for 1 hour), temperature rise(0.2° C./min), 0° C. (kept for 1 hour), temperature rise (0.2° C./min)20° C. (kept for 1 hour), temperature drop (−0.2° C./min), 0° C. (keptfor 1 hour), temperature drop (−0.2° C./min), and −20° C. to visuallyobserve the occurrence of precipitates of the liquid crystal compositionbased on the following four levels:

A: No precipitates were observed for 600 hours or more

B: No precipitates were observed for 300 hours or more

C: Precipitates were observed within 150 hours

D: Precipitates were observed within 75 hours

Example 1 and Comparative Examples 1 and 2

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 1.

TABLE 1 Comparative Comparative Example 1 Example 1 Example 2 Tni (° C.)85.0 79.2 79.4 Δn 0.098 0.094 0.100 Δε 10.1 9.9 10.7 η (mPa · s) 17 1617 γ1 (mPa · s) 99 92 100 Formula (26.2) 15 15 15 Formula (2.2) 30 30 30Formula (11.1) 20 20 20 Formula (28.3) 5 10 5 Formula (37.2) 5 0 5Formula (44.2) 5 5 0 Formula (28.5) 10 10 10 Formula (44.1) 5 5 0Formula (1.3) 5 5 5 Formula (45.2) 0 0 10

In Table 1, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Comparative Example 1 is a liquid crystal composition containing acompound represented by the formula (28.3) substituted for a compound(compound represented by the formula (37.2)) contained in a liquidcrystal composition of Example 1 and represented by the general formula(i). Comparing physical property values of Example 1 with those ofComparative Example 1, Tni is decreased by removing the compoundrepresented by the general formula (i). Therefore, Example 1 has ahigher Tni temperature and can be used over a wider temperature range.

Comparative Example 2 is a liquid crystal composition containing acompound represented by the formula (45.2) substituted for compounds(compounds represented by the formula (44.1) and the formula (44.2))contained in the liquid crystal composition of Example 1 and representedby the general formula (ii). Comparing the results of Example 1 withthose of Comparative Example 2, Tni is greatly decreased by removing thecompounds represented by the general formula (ii), and further Δn and Δ∈are increased, while a value of γ1 is increased.

Examples 2 to 4

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 2.

TABLE 2 Example 2 Example 3 Example 4 Tni (° C.) 87.9 87.6 88.3 Δn 0.0950.094 0.097 Δε 9.4 8.9 9.7 η (mPa · s) 15 15 16 γ1 (mPa · s) 88 81 95Formula (26.2) 15 15 15 Formula (2.2) 30 30 30 Formula (11.1) 20 20 20Formula (28.3) 10 10 8 Formula (11.2) 5 5 5 Formula (37.2) 5 5 5 Formula(44.2) 5 3 7 Formula (28.5) 10 12 10

In Table 2, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Example 5 and Comparative Examples 3 and 4

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 3.

TABLE 3 Comparative Comparative Example 5 Example 3 Example 4 Tni (° C.)93.9 96.8 90.9 Δn 0.125 0.130 0.121 Δε 21.7 26.5 20.6 η (mPa · s) 44 6239 γ1 (mPa · s) 230 289 198 Formula (2.2) 35 35 35 Formula (1.3) 15 1515 Formula (11.1) 5 5 5 Formula (28.3) 5 5 10 Formula (26.2) 10 10 10Formula (45.2) 5 10 10 Formula (44.1) 5 5 0 Formula (44.2) 5 5 0 Formula(31.2) 5 10 5 Formula (39.2) 5 0 5 Formula (38.2) 5 0 5

In Table 3, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Comparative Example 3 is a liquid crystal composition containingcompounds represented by the formula (45.2) and the formula (31.2)substituted for compounds (compounds represented by the formula (39.2)and the formula (38.2)) contained in a liquid crystal composition ofExample 5 and represented by the general formula (i). Comparing physicalproperty values of Example 5 with those of Comparative Example 3, avalue of η and a value or γ1 are significantly increased by removing thecompounds represented by the general formula (i). Therefore, Example 5has lower viscosity and can achieve fast response when used in a liquidcrystal display device.

Comparative Example 4 is a liquid crystal composition containingcompounds represented by the formula (28.3) and the formula (45.2)substituted for compounds (compounds represented by the formula (44.1)and the formula (44.2)) contained in the liquid crystal composition ofExample 5 and represented by the general formula (ii). Comparing theresults of Example 5 with those of Comparative Example 4, Tni isdecreased by removing the compounds represented by the general formula(ii), and further Δn and Δ∈ are also decreased.

Examples 6 to 8

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 4.

TABLE 4 Example 6 Example 7 Example 8 Tni (° C.) 94.8 95.1 96.5 Δn 0.1210.123 0.126 Δε 17.1 19.2 21.0 η (mPa · s) 35 40 46 γ1 (mPa · s) 190 222245 Formula (2.2) 39 40 35 Formula (1.3) 17 15 15 Formula (11.1) 5 5 5Formula (28.3) 2 2 2 Formula (26.2) 8 8 8 Formula (45.2) 4 4 5 Formula(44.1) 4 6 6 Formula (44.2) 4 6 6 Formula (31.2) 6 6 6 Formula (39.2) 64 6 Formula (38.2) 5 4 6

In Table 4, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Example 9 and Comparative Examples 5 and 6

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 5.

TABLE 5 Comparative Comparative Example 9 Example 5 Example 6 Tni (° C.)94.4 85.6 92.5 Δn 0.111 0.105 0.107 Δε 13.2 13.4 11.6 η (mPa · s) 19 1815 γ1 (mPa · s) 126 121 95 Formula (26.2) 10 10 10 Formula (11.1) 5 5 5Formula (45.2) 5 5 10 Formula (28.3) 5 10 10 Formula (37.2) 5 0 5Formula (44.2) 8 10 0 Formula (28.5) 8 10 10 Formula (44.1) 7 10 0Formula (39.2) 7 0 10 Formula (2.2) 30 30 30 Formula (1.3) 10 10 10

In Table 5, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Comparative Example 5 is a liquid crystal composition containingcompounds represented by the formula (44.2), the formula (28.5), and theformula (44.1) substituted for compounds (compounds represented by theformula (37.2) and the formula (39.2)) contained in a liquid crystalcomposition of Example 9 and represented by the general formula (i).Comparing physical property values of Example 9 with those ofComparative Example 5, a temperature of Tni is significantly decreasedby removing the compounds represented by the general formula (i).Therefore, Example 9 has a higher Tni temperature and can be used in awider temperature range.

Comparative Example 6 is a liquid crystal composition containingcompounds represented by the formula (45.2), the formula (28.3), theformula (28.5), and the formula (39.2) substituted for compounds(compounds represented by the formula (44.1) and the formula (44.2))contained in the liquid crystal composition of Example 9 and representedby the general formula (ii). Comparing the results of Example 9 withthose of Comparative Example 6, Tni is decreased by removing thecompounds represented by the general formula (ii), and further Δ∈ isalso decreased.

Examples 10 to 12

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 6.

TABLE 6 Example 10 Example 11 Example 12 Tni (° C.) 89.9 87.1 94.2 Δn0.105 0.105 0.105 η (mPa · s) 14 15 15 γ1 (mPa · s) 70 75 82 Formula(26.2) 9 9 6 Formula (1.3) 8 8 8 Formula (11.1) 17 17 17 Formula (45.2)5 5 5 Formula (11.2) 9 9 9 Formula (37.2) 7 4 7 Formula (44.2) 4 7 7Formula (2.4) 10 10 10 Formula (31.2) 3 3 3 Formula (2.3) 11 11 11Formula (3.3) 4 4 4 Formula (41.2) 1 1 1 Formula (19.2) 1 1 1 Formula(6.3) 11 11 11

In Table 6, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Examples 13 to 15

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 7.

TABLE 7 Example 13 Example 14 Example 15 Tni (° C.) 91.0 94.2 95.2 Δn0.100 0.099 0.102 Δε 9.0 8.5 9.6 γ1 (mPa · s) 90 84 111 Formula (26.2) 77 7 Formula (1.3) 15 15 15 Formula (2.2) 30 30 30 Formula (28.3) 7 7 7Formula (11.2) 12 12 12 Formula (45.3) 7 6 7 Formula (37.2) 2 5 8Formula (44.2) 6 4 6 Formula (45.4) 3 3 3 Formula (31.2) 11 11 5

In Table 7, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Examples 16 to 18

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 8.

TABLE 8 Example 16 Example 17 Example 18 Tni (° C.) 118.2 118.4 116.5 Δn0.130 0.134 0.126 Δε 10.4 15.0 9.7 η (mPa · s) 24 31 21 γ1 (mPa · s) 125167 108 Formula (26.2) 15 15 15 Formula (1.3) 10 10 10 Formula (11.1) 156 15 Formula (45.2) 5 5 5 Formula (11.2) 10 10 10 Formula (37.2) 5 8 4Formula (44.2) 5 8 3 Formula (44.1) 5 8 3 Formula (2.3) 15 15 15 Formula(23.1) 5 5 5 Formula (23.2) 5 5 5 Formula (5.3) 5 5 5 Formula (28.3) 0 05

In Table 8, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Examples 19 to 21

Compositions were prepared by using compounds represented by chemicalformulae below, and physical properties thereof were measured. Theresults are shown in Table 9.

TABLE 9 Example 19 Example 20 Example 21 Tni (° C.) 87.4 87 87.8 Δn0.105 0.105 0.105 Δε 9.5 9.5 9.5 γ1 (mPa · s) 96 96 96 Formula (26.2) 1010 10 Formula (1.3) 7 7 7 Formula (2.2) 25 25 25 Formula (11.1) 15 15 15Formula (45.2) 5 5 5 Formula (11.2) 8 8 8 Formula (44.2) 5 3 7 Formula(28.5) 5 5 5 Formula (44.1) 5 7 3 Formula (54.2) 5 5 5 Formula (28.3) 1010 10

In Table 9, a numerical value of each of the formulae represents a ratio(unit: % by mass) of each of the compounds contained in eachcomposition.

Evaluations of initial VHR, VHR after heating (150° C. for 1 hour),image sticking, volatility, process adaptability, and solubility at alow temperature of the liquid crystal composition of each of theexamples are described.

TABLE 10 Example Example Example Example Example Example Example 2 6 910 13 16 19 Initial VHR (%) 99.2 99.3 99.1 99.2 99.1 99.4 99.3 VHR afterheating (%) 98.0 98.2 98.2 98.1 98.3 98.3 98.2 Image sticking A B B B AA A Volatility A B B A A A A Process adaptability A A A A A A ASolubility at low B B A B B B B temperature

As a result of the same evaluation conducted for the liquid crystalcompositions of the examples other than Examples 2, 6, 9, 10, 13, 16,and 19 shown in the above table, good results were obtained.

The configuration and combination in each of the embodiments describedabove are only examples, and addition, omission, replacement, and othermodifications of the configuration can be made within a range notdeviating from the gist of the present invention. Also, the presentinvention is not limited to the embodiments and is limited only by thescope of the claims.

INDUSTRIAL APPLICABILITY

A liquid crystal composition according to the present invention can bewidely applied to the field of a liquid crystal display device andliquid crystal display.

REFERENCE SIGNS LIST

100 . . . first substrate, 102 . . . TFT layer, 103 . . . pixelelectrode, 104 . . . passivation film, 105 . . . first alignment film,200 . . . second substrate, 201 . . . planarization film (overcoatlayer), 202 . . . black matrix, 203 . . . color filter, 204 . . .transparent electrode, 205 . . . second alignment film, 301 . . .sealing material, 302 . . . projection (columnar spacer), 303 . . .liquid crystal layer, 304 . . . projection (columnar spacer), 401 . . .mask pattern, 402 . . . resin layer, L . . . light

1. A liquid crystal composition comprising any one or two or more ofcompounds represented by general formula (i) below and any one or two ormore of compounds represented by general formula (ii) below,

(in the formulae, R^(11a) and R^(21a) each independently represent analkyl group having 1 to 8 carbon atoms; one or nonadjacent two or more—CH₂— in the alkyl group may be each independently substituted by—CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—; one or two or more hydrogenatoms in the alkyl group may be each independently substituted by afluorine atom or a chlorine atom; m¹¹ represents 1 or 2; A¹¹ representsa trans-1,4-cyclohexylene group or a 1,4-phenylene group which may havea fluorine atom or a chlorine atom substituted for a hydrogen atom; whenm¹¹ is 1, A¹¹ represents a 1,4-phenylene group which may have a fluorineatom or a chlorine atom substituted for a hydrogen atom; when m¹¹ is 2,a plurality of A¹¹ may be the same or different, and at least one A¹¹represents a 1,4-phenylene group which may have a fluorine atom or achlorine atom substituted for a hydrogen atom; X¹¹ represents a hydrogenatom, a fluorine atom, or a chlorine atom; X¹² represents a hydrogenatom, a fluorine atom, a chlorine atom, a cyano group, —CF₃, or —OCF₃;m²¹ represents 0 or 1; X²¹, X²², X²³, and X²⁴ each independentlyrepresent a hydrogen atom, a fluorine atom, or a chlorine atom; and X²⁵represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyanogroup, —CF₃, or —OCF₃).
 2. The liquid crystal composition according toclaim 1, wherein m¹¹ in the general formula (i) is
 2. 3. The liquidcrystal composition according to claim 1, comprising two or morecompounds represented by the general formula (i).
 4. The liquid crystalcomposition according to claim 1, comprising two or more compoundsrepresented by the general formula (ii).
 5. The liquid crystalcomposition according to claim 1, comprising a compound represented bygeneral formula (L) below,

(in the formula, R^(L1) and R^(L2) each independently represent an alkylgroup having 1 to 8 carbon atoms; one or nonadjacent two or more —CH₂—in the alkyl group may be each independently substituted by —CH═CH—,—C≡C—, —O—, —CO—, —COO—, or —OCO—; OL represents 0, 1, 2, or 3; B^(L1),B^(L2), and B^(L3) each independently represent a group selected fromthe group consisting of: (a) a 1,4-cyclohexylene group (one —CH₂— ornonadjacent two or more —CH₂— present in the group may be substituted by—O—); and (b) a 1,4-phenylene group (one —CH═ or nonadjacent two or more—CH═ present in the group may be substituted by —N═), and one and/or twoor more hydrogen atoms in the group (a) and the group (b) may be eachindependently substituted by a cyano group, a fluorine atom, or achlorine atom; L^(L1) and L^(L2) each independently represent a singlebond, —CH₂CH₂—, —(CH₂)₄—, —OCH₂—, —CH₂O—, —COO—, —OCO—, —OCF₂—, —CF₂O—,—CH═N—N═CH—, —CH═CH—, —CF═CF—, or —C≡C—; and when OL is 2 or 3, and aplurality of L^(L2) are present, L^(L2) may be the same or different,and when OL is 2 or 3, and a plurality of B^(L3) are present, B^(L3) maybe the same or different).
 6. The liquid crystal composition accordingto claim 1, comprising a compound represented by general formula (M)below,

(in the formula, R^(M1) represents an alkyl group having 1 to 8 carbonatoms; one or nonadjacent two or more —CH₂— in the alkyl group may beeach independently substituted by —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or—OCO—; PM represents 0, 1, 2, 3, or 4; C^(M1) and C^(M2) eachindependently represent a group selected from the group consisting of:(d) a 1,4-cyclohexylene group (one —CH₂— or nonadjacent two or more—CH₂— present in the group may be substituted by —O— or —S—); and (e) a1,4-phenylene group (one —CH═ or nonadjacent two or more —CH═ present inthe group may be substituted by —N═), and one and/or two or morehydrogen atoms in the group (d) and the group (e) may be eachindependently substituted by a cyano group, a fluorine atom, or achlorine atom; K^(M1) and K^(M2) each independently represent a singlebond, —CH₂CH₂—, —(CH₂)₄—, —OCH₂—, —CH₂O—, —OCF₂—, —CF₂O—, —COO—, —OCO—,or —C≡C—; when PM is 2, 3, or 4, and a plurality of K^(M1) are present,K^(M1) may be the same or different, and when PM is 2, 3, or 4, and aplurality of C^(M2) are present, C^(M2) may be the same or different;X^(M1) and X^(M3) each independently represent a hydrogen atom, achlorine atom, or a fluorine atom; and X^(M2) represents a hydrogenatom, a fluorine atom, a chlorine atom, a cyano group, a trifluoromethylgroup, a fluoromethoxy group, a difluoromethoxy group, atrifluoromethoxy group, or a 2,2,2-trifluoroethyl group, with thecompounds represented by the general formula (i) and the general formula(ii) being excluded).
 7. A liquid crystal display device comprising theliquid crystal composition according to claim
 1. 8. A liquid crystaldisplay device for an IPS mode, an OCB mode, an ECB mode, a VA mode, ora FFS mode comprising the liquid crystal composition according toclaim
 1. 9. A liquid crystal display comprising the liquid crystaldisplay device according to claim
 7. 10. A liquid crystal displaycomprising the liquid crystal display device according to claim 8.